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  • 1.
    Adeel, Muhammad
    et al.
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, 30172, Venice-Mestre, Italy. Pathology Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, 33081, Aviano, Italy.
    Canzonieri, Vincenzo
    Pathology Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, 33081, Aviano, Italy. Department of Medical, Surgical and Health Sciences, University of Trieste, 34127, Trieste, Italy.
    Daniele, Salvatore
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, 30172, Venice-Mestre, Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, 30172, Venice-Mestre, Italy.
    Rizzolio, Flavio
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, 30172, Venice-Mestre, Italy. Pathology Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, 33081, Aviano, Italy.
    Rahman, Md. Mahbubur
    Department of Energy and Materials, Konkuk University, Chungju, 27478, Republic of Korea.
    2D metal azolate framework as nanozyme for amperometric detection of glucose at physiological pH and alkaline medium2021Ingår i: Microchimica Acta, ISSN 0026-3672, E-ISSN 1436-5073, Vol. 188, nr 3, artikel-id 77Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The synthesis of Co-based two-dimensional (2D) metal azolate framework nanosheets (MAF-5-CoII NS) is described using a simple hydrothermal method. The product was isostructural to MAF-5 (Zn). The as-prepared MAF-5-CoII NS exhibited high surface area (1155 m2/g), purity, and crystallinity. The MAF-5-CoII NS–modified screen-printed electrode (MAF-5-CoII NS/SPE) was used for nonenzymatic detection of glucose in diluted human blood plasma (BP) samples with phosphate buffer saline (PBS, pH 7.4) and NaOH (0.1 M, pH 13.0) solutions. The MAF-5-CoII NS nanozyme displayed good redox activity in both neutral and alkaline media with the formation of CoII/CoIII redox pair, which induced the catalytic oxidation of glucose. Under the optimized detection potential, the sensor presented a chronoamperometric current response for the oxidation of glucose with two wide concentration ranges in PBS-diluted (62.80 to 180 μM and 305 to 8055 μM) and NaOH-diluted (58.90 to 117.6 μM and 180 to 10,055 μM) BP samples, which were within the limit of blood glucose levels of diabetic patients before (4.4–7.2 mM) and after (10 mM) meals (recommended by the American Diabetes Association). The sensor has a limit of detection of ca. 0.25 and 0.05 μM, respectively, and maximum sensitivity of ca. 36.55 and 1361.65 mA/cm2/mM, respectively, in PBS- and NaOH-diluted BP samples. The sensor also displayed excellent stability in the neutral and alkaline media due to the existence of hydrophobic linkers (2-ethyl imidazole) in the MAF-5-CoII NS, good repeatability and reproducibility, and interference-free signals. Thus, MAF-5-CoII NS is a promising nanozyme for the development of the disposable type of sensor for glucose detection in human body fluids.

  • 2.
    Afanasiev, Sergey V.
    et al.
    Joint Institute for Nuclear Research Joliot-Curie 6.
    Afonin, Alexander G.
    Institute of High Energy Physics - Moscow Region.
    Ambrosi, Giovanni
    INFN Sezione di Perugia.
    Azzarello, Philipp
    INFN Sezione di Perugia.
    Baranov, Vladimir T.
    Institute of High Energy Physics - Moscow Region.
    Baricordi, Stefano
    INFN Sezione di Ferrara.
    Battiston, Roberto
    INFN Sezione di Perugia.
    Bertucci, Bruna
    INFN Sezione di Perugia.
    Bolognini, Davide
    Università dell'Insubria.
    Burger, William J.
    INFN Sezione di Perugia.
    Carnera, Alberto
    INFN Laboratori Nazionali di Legnaro.
    Cavoto, Gianluca
    INFN Sezione di Roma.
    Chesnokov, Yury A.
    Institute of High Energy Physics - Moscow Region.
    Dalpiaz, Pietro
    INFN Sezione di Ferrara.
    Della Mea, Gianantonio
    INFN Laboratori Nazionali di Legnaro.
    Denisov, Alexander S.
    Petersburg Nuclear Physics Institute.
    De Salvador, Davide
    INFN Laboratori Nazionali di Legnaro.
    Fiorini, Massimiliano
    INFN Sezione di Ferrara.
    Foggetta, Luca
    Università dell'Insubria.
    Gavrikov, Yury A.
    Petersburg Nuclear Physics Institute.
    Guidi, Vincenzo
    INFN Sezione di Ferrara.
    Hasan, Said
    Università dell'Insubria.
    Ionica, Maria
    INFN Sezione di Perugia.
    Ivanov, Yuri M.
    Petersburg Nuclear Physics Institute.
    Ivochkin, Vladimir G.
    Petersburg Nuclear Physics Institute.
    Vomiero, Alberto
    INFN Laboratori Nazionali di Legnaro.
    Zuccon, Paolo
    INFN Sezione di Perugia.
    Experimental apparatus to study crystal channeling in an external SPS beamline2007Ingår i: Proceedings of SPIE, the International Society for Optical Engineering, ISSN 0277-786X, E-ISSN 1996-756X, Vol. 6634Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For the new generation of high intensity hadronic machines as, for instance, LHC, halo collimation is a necessary issue for the accelerator to operate at the highest possible luminosity and to prevent the damage of superconductor magnets.1 We propose an experiment aimed to systematic study of the channeling phenomenology and of the newly observed "volume reflection" effect. This experiment will be performed for an external SPS beamline and will make use of a primary proton beam with 400 GeV/c momentum and very small (∼ 3 μrad) divergence. The advantage of a proposed experiment is precise tracking of particles that interacted with a crystal, so that to determine the single-pass efficiency for all the processes involved. For this purpose, a telescope equipped with high-resolution silicon microstrip detectors will be used. New generation silicon crystals and an extra-precise goniometer are mandatory issues. Main goal of the experiment is to get the precise information on channeling of relativistic particles and, ultimately, on the feasibility of such technique for halo collimation at LHC. In this contribution we review the status of the setting-up of experimental apparatus and its future development in sight of the planned run in September 2006.

  • 3.
    Aftab, Umair
    et al.
    Department of Metallurgy and Materials Engineering, Mehran University of Engineering and Technology, Jamshoro, Sindh, 76080, Pakistan.
    Tahira, Aneela
    Department of Science and Technology, Campus Norrköping, Linköping University, Norrköping, SE-60174, Sweden.
    Gradone, Alessandro
    CNR-IMM, Via Piero Gobetti 101, Bologna, 40129, Italy. Chemistry Department “G.Ciamician”, University of Bologna, Bologna, 40126, Italy.
    Morandi, Vittorio
    CNR-IMM, Via Piero Gobetti 101, Bologna, 40129, Italy.
    Abro, Muhammad Ishaq
    Department of Metallurgy and Materials Engineering, Mehran University of Engineering and Technology, Jamshoro, Sindh, 76080, Pakistan.
    Baloch, Muhammad Moazam
    Department of Metallurgy and Materials Engineering, Mehran University of Engineering and Technology, Jamshoro, Sindh, 76080, Pakistan.
    Bhatti, Adeel Liaquat
    Institute of Physics University of Sindh, Jamshoro, Sindh, 76080, Pakistan.
    Nafady, Ayman
    Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia, Mestre, 30172, Italy.
    Ibupoto, Zafar Hussain
    Dr. M.A Kazi Institute of Chemistry University of Sindh, Jamshoro, Sindh, 76080 Pakistan.
    Two step synthesis of TiO2–Co3O4 composite for efficient oxygen evolution reaction2021Ingår i: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 46, nr 13, s. 9110-9122Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For an active hydrogen gas generation through water dissociation, the sluggish oxygen evolution reaction (OER) kinetics due to large overpotential is a main hindrance. Herein, a simple approach is used to produce composite material based on TiO2/Co3O4 for efficient OER and overpotential is linearly reduced with increasing amount of TiO2. The scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) investigations reveal the wire like morphology of composite materials, formed by the self-assembly of nanoparticles. The titania nanoparticles were homogenously distributed on the larger Co3O4 nanoparticles. The powder x-ray diffraction revealed a tetragonal phase of TiO2 and the cubic phase of Co3O4 in the composite materials. Composite samples with increasing TiO2 content were obtained (18%, 33%, 41% and 65% wt.). Among the composites, cobalt oxide-titanium oxide with the highest TiO2 content (CT-20) possesses the lowest overpotential for OER with a Tafel slope of 60 mV dec−1 and an exchange current density of 2.98 × 10−3A/cm2. The CT-20 is highly durable for 45 h at different current densities of 10, 20 and 30 mA/cm2. Electrochemical impedance spectroscopy (EIS) confirmed the fast charge transport for the CT-20 sample, which potentially accelerated the OER kinetics. These results based on a two-step methodology for the synthesis of TiO2/Co3O4 material can be useful and interesting for various energy storage and energy conversion systems.

  • 4.
    Ahdikari, Rajesh
    et al.
    Centre for Energy, Materials and Telecommunications, Institut National de la Recherche Scientifique, 1650 Boul. Lionel-Boulet, Varennes.
    Jin, Lei
    Institut National de la Recherche Scientifique Energie Varennes.
    Pardo, Fabola Navarro
    Centre for Energy, Materials and Telecommunications, Institut National de la Recherche Scientifique, Varennes.
    Benetti, Daniele
    INRS, Quebec University, Varennes, Centre for Energy, Materials and Telecommunications, Institut National de la Recherche Scientifique, Varennes.
    Otabi, Bandar Al
    Department of Electrical and Computer Engineering, McGill University, Montreal.
    Vanka, Srinivas
    Department of Electrical and Computer Engineering, McGill University, Montreal.
    Zhao, Haiguang
    Institut National de la Recherche Scientifique Energie Varennes, INRS Centre for Energy, Materials and Telecommunications, CNR-INO SENSOR Lab, Centre for Energy, Materials and Telecommunications, Institut National de la Recherche Scientifique, 1650 Boul. Lionel-Boulet, Varennes.
    Mi, Zetian
    Department of Electrical and Computer Engineering, McGill University, Montreal.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Rosei, Frederico
    Institut National de la Recherche Scientifique Energie Varennes, Centre for Energy, Materials and Telecommunications, Institut National de la Recherche Scientifique, 1650 Boul. Lionel-Boulet, Varennes.
    High Efficiency, Pt-free Photoelectrochemical Cells for Solar Hydrogen Generation based on “Giant” Quantum Dots2016Ingår i: Nano Energy, ISSN 2211-2855, Vol. 27, s. 265-274Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quantum dot (QD) sensitized TiO2 is considered as a highly promising photoanode material for photoelectrochemical (PEC) solar hydrogen production. However, due to its limited stability, the photoanode suffers from degradation of its long-term PEC performance. Here, we report the design and characterization of a high-efficiency and long-term stable Pt-free PEC cell. The photoanode is composed of a mesoporous TiO2 nanoparticle film sensitized with “giant” core@shell QDs for PEC solar hydrogen generation. The thick shell enhances light absorption in the visible range, increases the stability of the QDs and does not inhibit charge separation, injection and transport, needed for proper operation of the device. We prepared thin films of Cu2S nanoflakes through a simple and reproducible procedure, and used them as counter-electrodes replacing the standard Pt film, resulting in equivalent performances of the PEC cell. We obtained an unprecedented photocurrent density (~10 mA/cm2) for “giant” QDs based PEC devices (and corresponding H2 generation) and a very promising stability, indicating that the proposed cell architecture is a good candidate for long-term stable QD-based PEC solar hydrogen generation.

  • 5.
    Akbar, Kamran
    et al.
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia Mestre, 30172 Italy.
    Moretti, Elisa
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia Mestre, 30172 Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia Mestre, 30172 Italy.
    Carbon Dots for Photocatalytic Degradation of Aqueous Pollutants: Recent Advancements2021Ingår i: Advanced Optical Materials, ISSN 2162-7568, E-ISSN 2195-1071, Vol. 9, nr 17, artikel-id 2100532Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The immense progress of humanity on the technological, domestic, and industrial fronts comes at the cost of polluting the planet. Aquatic pollution is particularly dangerous since all life forms are directly linked to it. Each year tons of industrial and domestic pollutants make their way into aqueous systems. Efficient removal/degradation of these pollutants is of prime importance for the sustainable future. Among many technologies, photodegradation is an emerging and promising method for the successful removal of aqueous pollutants since it is powered by abundant solar light. The last decade had shown that carbon dots are among the most promising materials that can be utilized as an efficient tool to derive various solar-driven chemical reactions. Carbon dots possess unique photophysical and chemical properties such as light-harvesting over a broad-spectrum region, upconversion photoluminescence, photosensitizers, chemical inertness, and bivalent redox character, etc. The ease of synthesis of carbon dots at low cost also contributes hugely to their utilizations as an efficient photocatalyst for the degradation of aqueous pollutants. This review summarizes the recent progress made in the field of photodegradation of aqueous pollutants with the aid of carbon dots and their hybrids, highlighting the critical role carbon dots can play in the field. 

  • 6.
    Alberoni, Chiara
    et al.
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia Mestre, Italy.
    Barroso-Martín, Isabel
    Departamento de Química Inorgánica, Cristalografía y Mineralogía (Unidad Asociada al ICP-CSIC), Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos, 29071 Málaga, Spain.
    Infantes-Molina, Antonia
    Departamento de Química Inorgánica, Cristalografía y Mineralogía (Unidad Asociada al ICP-CSIC), Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos, 29071 Málaga, Spain.
    Rodríguez-Castellón, Enrique
    Departamento de Química Inorgánica, Cristalografía y Mineralogía (Unidad Asociada al ICP-CSIC), Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos, 29071 Málaga, Spain.
    Talon, Aldo
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia Mestre, Italy.
    Zhao, Haiguang
    Qingdao University – College of Physics & State Key Laboratory of Bio-Fibers and Eco-Textiles, 308 Ningxia Road, Qingdao 266071, P. R. China.
    You, Shujie
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia Mestre, Italy.
    Moretti, Elisa
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, Venezia Mestre, Italy.
    Ceria doping boosts methylene blue photodegradation in titania nanostructures2021Ingår i: Materials Chemistry Frontiers, E-ISSN 2052-1537, Vol. 5, nr 11, s. 4138-4152Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ceria-doped titania photocatalysts (ceria loading 0.25–5.0 wt%) were synthesized by hydrothermal methods for water remediation. Nanotubes (CeTNTx) and nanoparticles (CeTNPx) were obtained. Ceria doping was applied to tune the electronic properties of nanostructured titania, boosting its photocatalytic activity. CeTNT nanostructures contained anatase as the only titania phase, whereas the CeTNP series consisted of both anatase and rutile polymorphs. The Ce addition induced a decrease in the energy gap, allowing enhancement of visible light harvesting. The photodegradation of methylene blue, MB, in aqueous solution was chosen to study the influence of the morphology and the ceria loading on the photocatalytic response, under UV and solar light. Both CeO2–TiO2 nanoparticles and nanotubes were found to be very active under UV light. The highest MB degradation rates were obtained for the 0.25 wt% CeO2 doping, for both nanotubes and nanoparticles (0.123 and 0.146 min−1, respectively), able to photodegrade completely the dye after 120 min. The two samples are stable after a 3-cycle reusability test. The photo-response under simulated solar light confirmed that doping titania with ceria allows harvesting visible light absorption, enhancing its photoactivity. A maximum efficiency of 85% under simulated sunlight at a degradation rate of 0.054 min−1 was obtained. Transient photoluminescence confirmed that MB acts as a charge scavenger for the composite system. These results pointed out ceria-doped titania nanostructures as a promising class of photocatalysts for the degradation of dyes and other hazardous organic compounds in wastewater.

  • 7.
    Alvi, Sajid Ali
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Ghamgosar, Pedram
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Rigoni, Federica
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Adaptive nanolaminate coating by atomic layer deposition2019Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 692, artikel-id 137631Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Atomic layer deposition (ALD) was used to deposit ZnO/Al2O3/V2O5 nanolaminate coatings to demonstrate a coating system with temperature adaptive frictional behaviour. The nanolaminate coating exhibited excellent conformity and crack-free coating of thickness 110 nm over Inconel 718 substrate. The ALD trilayer coating showed a hardness and elastic modulus of 12 GPa and 193 GPa, respectively. High-temperature tribology of the nanolaminate trilayer was tested against steel ball in dry sliding condition at 25 °C (room temperature, RT), 200 °C, 300 °C, and 400 °C. It was found that the nanolaminate coating showed a low coefficient of friction (COF) and wear rate at RT and 300 °C. The trilayer coating was found intact and stable at all temperatures during the friction tests. The adaptability of nanolaminate coating with the temperature was verified by performing the cyclic friction test at 300 °C and RT. The low COF and wear rate had been attributed to the (100) and (002) basal plane sliding of ZnO top layer, and the interlayer sliding of weakly bonded planes parallel to (001) plane in V2O5 bottom layer. Furthermore, even after the removal of ZnO coating during the tribotest, the bottom V2O5 layer coating stabilized the COF and wear rate at RT and 300 °C.

  • 8.
    Alvi, Sajid
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Jarzabek, Dariusz M.
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Gilzad Kohan, Mojtaba
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Hedman, Daniel
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Jenczyk, Piotr
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Natile, Marta Maria
    CNR—Institute of Condensed Matter Chemistry and Technologies for Energy (ICMATE), I-16149 Genoa, Italy. Department of Chemical Sciences, University of Padova, 35131 Padova, Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Synthesis and Mechanical Characterization of a CuMoTaWV High-Entropy Film by Magnetron Sputtering2020Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 12, nr 18, s. 21070-21079Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Development of high-entropy alloy (HEA) films is a promising and cost-effective way to incorporate these materials of superior properties in harsh environments. In this work, a refractory high-entropy alloy (RHEA) film of equimolar CuMoTaWV was deposited on silicon and 304 stainless-steel substrates using DC-magnetron sputtering. A sputtering target was developed by partial sintering of an equimolar powder mixture of Cu, Mo, Ta, W, and V using spark plasma sintering. The target was used to sputter a nanocrystalline RHEA film with a thickness of ∼900 nm and an average grain size of 18 nm. X-ray diffraction of the film revealed a body-centered cubic solid solution with preferred orientation in the (110) directional plane. The nanocrystalline nature of the RHEA film resulted in a hardness of 19 ± 2.3 GPa and an elastic modulus of 259 ± 19.2 GPa. A high compressive strength of 10 ± 0.8 GPa was obtained in nanopillar compression due to solid solution hardening and grain boundary strengthening. The adhesion between the RHEA film and 304 stainless-steel substrates was increased on annealing. For the wear test against the E52100 alloy steel (Grade 25, 700–880 HV) at 1 N load, the RHEA film showed an average coefficient of friction (COF) and wear rate of 0.25 (RT) and 1.5 (300 °C), and 6.4 × 10–6 mm3/N m (RT) and 2.5 × 10–5 mm3/N m (300 °C), respectively. The COF was found to be 2 times lower at RT and wear rate 102 times lower at RT and 300 °C than those of 304 stainless steel. This study may lead to the processing of high-entropy alloy films for large-scale industrial applications.

  • 9.
    Alvi, Sajid
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Physics, Chalmers University of Technology, SE‐412 96 Göteborg, Sweden.
    Milczarek, Michal
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Jarzabek, Dariusz M.
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Hedman, Daniel
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Research Center for Computational Design of Advanced Functional Materials, National Institute of Advanced Industrial Science and Technology (AIST), Central 2, 1‐1‐1 Umezono, Tsukuba, Ibaraki, 305‐8568 Japan; Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan, 44919 Republic of Korea.
    Gilzad Kohan, Mojtaba
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Levintant-Zayonts, Neonila
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Via Torino 155, 30172 Mestre Venezia, Italy.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Enhanced mechanical, thermal and electrical properties of high‐entropy HfMoNbTaTiVWZr thin film metallic glass and its nitrides2022Ingår i: Advanced Engineering Materials, ISSN 1438-1656, E-ISSN 1527-2648, Vol. 24, nr 9, artikel-id 2101626Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The inception of high-entropy alloy promises to push the boundaries for new alloy design with unprecedented properties. This work reports entropy stabilisation of an octonary refractory, HfMoNbTaTiVWZr, high-entropy thin film metallic glass, and derived nitride films. The thin film metallic glass exhibited exceptional ductility of ≈60% strain without fracture and compression strength of 3 GPa in micro-compression, due to the presence of high density and strength of bonds. The thin film metallic glass shows thermal stability up to 750 °C and resistance to Ar-ion irradiation. Nitriding during film deposition of HfMoNbTaTiVWZr thin film of strong nitride forming refractory elements results in deposition of nanocrystalline nitride films with compressive strength, hardness, and thermal stability of up to 10 GPa, 18.7 GPa, and 950 °C, respectively. The high amount of lattice distortion in the nitride films leads to its insulating behaviour with electrical conductivity as low as 200 S cm−1 in the as-deposited film. The design and exceptional properties of the thin film metallic glass and derived nitride films may open up new avenues of development of bulk metallic glasses and the application of refractory-based high entropy thin films in structural and functional applications.

  • 10.
    Amin, Sidra
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan.Department of Chemistry, Shaheed Benazir Bhutto University, Shaheed Benazirabad, Pakistan.
    Tahira, Aneela
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Solangi, Amber
    National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan.
    Beni, Valerio
    RISE Acreo, Research Institute of Sweden, Norrköping, Sweden.
    Morante, J.R
    Catalonia Institute for Energy Research (IREC), Barcelona, Spain.
    Liu, Xianjie
    Department of Physics, Chemistry and Biology, Surface Physics and Chemistry, Linköping University, Faculty of Science & Engineering, Sweden.
    Falhman, Mats
    Department of Physics, Chemistry and Biology, Surface Physics and Chemistry, Linköping University, Faculty of Science & Engineering, Sweden.
    Mazzaro, Raffaello
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Ibupoto, Zafar
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Institute of Chemistry, University of Sindh, Jamshoro, Pakistan.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    A practical non-enzymatic urea sensor based on NiCo2O4 nanoneedles2019Ingår i: RSC Advances, E-ISSN 2046-2069, Vol. 9, nr 25, s. 14443-14451Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose a new facile electrochemical sensing platform for determination of urea, based on a glassy carbon electrode (GCE) modified with nickel cobalt oxide (NiCo2O4) nanoneedles. These nanoneedles are used for the first time for highly sensitive determination of urea with the lowest detection limit (1 μM) ever reported for the non-enzymatic approach. The nanoneedles were grown through a simple and low-temperature aqueous chemical method. We characterized the structural and morphological properties of the NiCo2O4 nanoneedles by TEM, SEM, XPS and XRD. The bimetallic nickel cobalt oxide exhibits nanoneedle morphology, which results from the self-assembly of nanoparticles. The NiCo2O4 nanoneedles are exclusively composed of Ni, Co, and O and exhibit a cubic crystalline phase. Cyclic voltammetry was used to study the enhanced electrochemical properties of a NiCo2O4 nanoneedle-modified GCE by overcoming the typical poor conductivity of bare NiO and Co3O4. The GCE-modified electrode is highly sensitive towards urea, with a linear response (R2 = 0.99) over the concentration range 0.01–5 mM and with a detection limit of 1.0 μM. The proposed non-enzymatic urea sensor is highly selective even in the presence of common interferents such as glucose, uric acid, and ascorbic acid. This new urea sensor has good viability for urea analysis in urine samples and can represent a significant advancement in the field, owing to the simple and cost-effective fabrication of electrodes, which can be used as a promising analytical tool for urea estimation.

  • 11.
    Amin, Sidra
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan. Department of Chemistry, Shaheed Benazir Bhutto University, Shaheed Benazirabad, Pakistan.
    Tahira, Aneela
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Solangi, Amber
    National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan.
    Mazzaro, Raffaello
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Ibupoto, Zafar
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Chemistry, Shaheed Benazir Bhutto University, Shaheed Benazirabad, Pakistan.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    A sensitive enzyme-free lactic acid sensor based on NiO nanoparticles for practical applications2019Ingår i: Analytical Methods, ISSN 1759-9660, E-ISSN 1759-9679, Vol. 11, s. 3578-3583Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A facile and efficient electrochemical sensing platform has been successfully exploited for the first time for the determination of lactic acid using a nickel oxide (NiO) nanoparticle-modified glassy carbon electrode (GCE). Nickel oxide nanoparticles were prepared by a chemical growth method using different quantities of arginine as a soft template. The structural and morphological properties of NiO nanoparticles were characterized by Raman spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Cyclic voltammetry (CV) was used to study the electrochemical properties of various samples. The modified electrode is highly sensitive and presents a linear response over a wide range (0.005–5 mM) of lactic acid concentrations in 0.1 M NaOH. The detection limit for the sensor was found to be 5.7 μM, and it exhibits good stability. Furthermore, the sensor shows excellent selectivity in the presence of common interfering species. The lactic acid sensor showed good viability for lactic acid analysis in real samples (milk, yogurt and red wine) and demonstrated significant advancement in sensor technology for practical applications.

  • 12.
    Amin, Sidra
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan. Department of Chemistry, Shaheed Benazir Bhutto University, Shaheed Benazirabad, Sindh Pakistan.
    Tahira, Aneela
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Solangi, Amber R.
    National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan.
    Mazzaro, Raffaello
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Institute for Microelectronics and Microsystems, National Research Council, Bologna, Italy.
    Ibupoto, Zafar Hussain
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Institute of Chemistry, University of Sindh, Jamshoro, Sindh Pakistan.
    Fatima, Almas
    National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro, Pakistan.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy.
    Functional Nickel Oxide Nanostructures for Ethanol Oxidation in Alkaline Media2020Ingår i: Electroanalysis, ISSN 1040-0397, E-ISSN 1521-4109, Vol. 32, nr 5, s. 1052-1059Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nickel oxide (NiO) nanostructures are employed in the basic medium for the oxidation of ethanol. A variety of NiO nanostructures are synthesized by wet chemical growth method, using different hydroxide (OH−) ion sources, particularly from ammonia, hexamethylenetetramine, urea and sodium hydroxide. The use of urea as (OH−) ion source results in flower‐like NiO structures composed by extremely thin nanowalls (thickness lower than 10 nm,), which demonstrated to be the most active for ethanol oxidation. All the samples exhibit NiO cubic phase, and no other impurity was detected. The cyclic voltammetry (CV) curves of NiO nanostructures were found linear over the concentration range 0.1–3.5 mM (R2=0.99) of ethanol, with the limit of detection estimated to be 0.013 mM for ethanol. The NiO nanostructures exhibit a selective signal towards ethanol oxidation in the presence of different members of alcohol family. The proposed NiO nanostructures showed a significant practicality for the reproducible and sensitive determination of ethanol from brandy, whisky, mixture of brandy and rum, and vodka samples. The nanomaterial was used as a surface modifying agent for the glassy carbon electrode and it showed a stable electro‐oxidation activity for the ethanol for 16 days. These findings indicate that the presented NiO nanomaterial can be applied in place of noble metals for ethanol sensing and other environmental applications (like fuel cells).

  • 13.
    Banari, Mohammad
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Faculty of Physics, Semnan University, P.O. Box: 35195-363, Semnan, Iran.
    Memarian, N.
    Faculty of Physics, Semnan University, P.O. Box: 35195-363, Semnan, Iran.
    Concina, Isabella
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Via Torino 155, 30172, Venezia, Mestre, Italy.
    UV photodetector study based on Ce: ZnO nanostructures with different concentration of Ce dopant2023Ingår i: Optical materials (Amsterdam), ISSN 0925-3467, E-ISSN 1873-1252, Vol. 146, artikel-id 114576Artikel i tidskrift (Refereegranskat)
  • 14.
    Banari, Mohammad
    et al.
    Faculty of Physics, Semnan University, P.O. Box: 35195-363, Semnan, Iran.
    Memarian, Nafiseh
    Faculty of Physics, Semnan University, P.O. Box: 35195-363, Semnan, Iran.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy.
    Effect of the seed layer on the UV photodetection properties of ZnO nanorods2021Ingår i: Materials Science & Engineering: B. Solid-state Materials for Advanced Technology, ISSN 0921-5107, E-ISSN 1873-4944, Vol. 272, artikel-id 115332Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ZnO seed layer, acting as nucleation center for the growth of ZnO nanorods (NRs), has strong impact on the optical and photodetection properties of ZnO-based UV photodetectors (PDs). In this paper, vertically aligned ZnO NRs were grown by varying the thickness of the seed layer in the range 50–125 nm, to investigate its influence on the recovery time of the PD. Single crystalline ZnO NRs were obtained as indicated by combined electron microscopy and X-ray diffraction analysis. The photoluminescence (PL) spectra proved that the lowest PL intensity (i.e.: the lowest recombination) belongs to the sample with seed layer thickness of 100 nm (labeled as NR-7). The carrier concentration of ZnO NR films was estimated from the slope of the Mott–Schottky plot. It was 1.49 × 10+20 cm−3 for seed layer thickness of 65 nm (NR-5), which was dramatically reduced to 5.44 × 10+17 cm−3 in the sample NR-9 (seed layer thickness 125 nm). Furthermore, the current-voltage (I-V) and chronoamperometric (I-t) analysis indicate a high UV responsivity under a UV irradiation. The fastest recovery time (0.1 s time decay constant) occurs in sample NR-7 (seed layer 100 nm thick). These results indicate that effective control of the electronic and optical properties in ZnO NRs can be obtained by proper tuning of the seed layer, enabling a simple and straightforward strategy to optimize NR functionality, depending on their planned use.

  • 15.
    Baratto, Camilla
    et al.
    University of Brescia and CNR-INFM SENSOR Laboratory, Brescia, Italy.
    Comini, Elisabetta
    University of Brescia and CNR-INFM SENSOR Laboratory, Brescia, Italy.
    Faglia, Guido
    University of Brescia and CNR-INFM SENSOR Laboratory, Brescia, Italy.
    Ferroni, Matteo
    University of Brescia and CNR-INFM SENSOR Laboratory, Brescia, Italy.
    Ponzoni, Andrea
    University of Brescia and CNR-INFM SENSOR Laboratory, Brescia, Italy.
    Vomiero, Alberto
    University of Brescia and CNR-INFM SENSOR Laboratory, Brescia, Italy.
    Sberveglieri, Giorgio
    University of Brescia and CNR-INFM SENSOR Laboratory, Brescia, Italy.
    Transparent Metal Oxide Semiconductors as Gas Sensors2010Ingår i: Transparent Electronics: From Synthesis to Applications, John Wiley and Sons , 2010, s. 417-442Kapitel i bok, del av antologi (Refereegranskat)
  • 16. Baricordi, S.
    et al.
    Biryukov, V. M.
    Institute for High Energy Physics.
    Carnera, A.
    Chesnokov, Yu A.
    Institute for High Energy Physics.
    Della Mea, G.
    University of Trento, Department of Materials Engineering and Industrial Technologies.
    Guidi, V.
    Ivanov, Yu M.
    Petersburg Institute for Nuclear Physics.
    Martinelli, G.
    Milan, E.
    Restello, S.
    INFN.
    Sambo, A.
    Scandale, W.
    CERN.
    Vomiero, Alberto
    Department of Physics, University of Padova.
    Low-energy-channeling surface analysis on silicon crystals designed for high-energy-channeling in accelerators2005Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 87, nr 9, artikel-id 94102Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Channeling of relativistic particles in bent Si crystals is a powerful technique for use with accelerators. Its efficiency can be found to be highly dependent on the state of the surface of the crystal steering the particles. We investigated the morphology and structure of the surface of the samples that have been used with high efficiency for channeling in accelerators. Low-energy channeling of 2 MeVα particles or protons was used as a probe. We found that mechanical treatment of the samples leads to a superficial damaged layer, which is correlated to efficiency limitations of the crystal in accelerators. In contrast, chemical etching, which was used to treat the surface of the most efficient crystals, leaves a surface with superior perfection. © 2005 American Institute of Physics.

  • 17.
    Baricordi, S.
    et al.
    Dipartimento di Fisica Sperimentale, Università di Torino.
    Guidi, V.
    Dipartimento di Fisica Sperimentale, Università di Torino.
    Mazzolari, A.
    Dipartimento di Fisica Sperimentale, Università di Torino.
    Martinelli, G.
    Dipartimento di Fisica Sperimentale, Università di Torino.
    Carnera, A.
    Dipartimento di Fisica Sperimentale, Università di Torino.
    De Salvador, D.
    Dipartimento di Fisica Sperimentale, Università di Torino.
    Sambo, A.
    Dipartimento di Fisica Sperimentale, Università di Torino.
    Della Mea, G.
    Dipartimento di Ingegneria dei Materiali, Università di Trento.
    Milan, R.
    INFN Laboratori Nazionali di Legnaro.
    Vomiero, Alberto
    INFM-CNR Sensor Lab.
    Scandale, W.
    European Organization for Nuclear Research.
    Optimal crystal surface for efficient channeling in the new generation of hadron machines2007Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 91, nr 6, artikel-id 61908Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The new generation of hadron machines may profitably take advantage of channeling for steering and collimation of high-energy particle beams. In that case, the requirements on the quality of the crystal surface are rather stringent in terms of both lattice perfection and roughness. Here, the authors show the structural and morphological characterizations of crystals fabricated through a method to achieve a surface that fulfills all needed specifications for application in hadron machines. © 2007 American Institute of Physics.

  • 18.
    Basu, Kaustubh
    et al.
    Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes.
    Benetti, Daniele
    Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes.
    Zhao, Haiguang
    Institut National de la Recherche Scientifique Energie Varennes, Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes.
    Jin, Lei
    Institut National de la Recherche Scientifique Energie Varennes, Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes.
    Vetrone, Fiorenzo
    Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Rosei, Frederico
    Institut National de la Recherche Scientifique Energie Varennes, Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes.
    Enhanced photovoltaic properties in dye sensitized solar cells by surface treatment of SnO2 photoanodes2016Ingår i: Scientific Reports, E-ISSN 2045-2322, Vol. 6, artikel-id 23312Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report the fabrication and testing of dye sensitized solar cells (DSSC) based on tin oxide (SnO2) particles of average size ~20 nm. Fluorine-doped tin oxide (FTO) conducting glass substrates were treated with TiOx or TiCl4 precursor solutions to create a blocking layer before tape casting the SnO2 mesoporous anode. In addition, SnO2 photoelectrodes were treated with the same precursor solutions to deposit a TiO2 passivating layer covering the SnO2 particles. We found that the modification enhances the short circuit current, open-circuit voltage and fill factor, leading to nearly 2-fold increase in power conversion efficiency, from 1.48% without any treatment, to 2.85% achieved with TiCl4 treatment. The superior photovoltaic performance of the DSSCs assembled with modified photoanode is attributed to enhanced electron lifetime and suppression of electron recombination to the electrolyte, as confirmed by electrochemical impedance spectroscopy (EIS) carried out under dark condition. These results indicate that modification of the FTO and SnO2 anode by titania can play a major role in maximizing the photo conversion efficiency

  • 19.
    Bemmerer, D.
    et al.
    INFN, Sezione di Padova, via Marzolo 8, 35131, Padova, Italy; Institut für Atomare Physik und Fachdidaktik, Technische Universität Berlin, Berlin, Germany.
    Confortola, F.
    Dipartimento di Fisica, Università di Genova, and INFN, Genova, Italy.
    Lemut, A.
    Dipartimento di Fisica, Università di Genova, and INFN, Genova, Italy.
    Bonetti, R.
    Istituto di Fisica, Università di Milano, and INFN, Milano, Italy.
    Broggini, C.
    INFN, Sezione di Padova, via Marzolo 8, 35131, Padova, Italy.
    Corvisiero, P.
    Dipartimento di Fisica, Università di Genova, and INFN, Genova, Italy.
    Costantini, H.
    Dipartimento di Fisica, Università di Genova, and INFN, Genova, Italy.
    Cruz, J.
    Centro de Fisica Nuclear da Universidade de Lisboa, Lisboa, Portugal.
    Formicola, A.
    Laboratori Nazionali del Gran Sasso, INFN, Assergi (AQ), Italy.
    Fülöp, Zs.
    ATOMKI, Debrecen, Hungary.
    Gervino, G.
    Dipartimento di Fisica Sperimentale, Università di Torino, and INFN, Torino, Italy.
    Guglielmetti, A.
    Istituto di Fisica, Università di Milano, and INFN, Milano, Italy.
    Gustavino, C.
    Laboratori Nazionali del Gran Sasso, INFN, Assergi (AQ), Italy.
    Gyürky, Gy.
    ATOMKI, Debrecen, Hungary.
    Imbriani, G.
    Dipartimento di Scienze Fisiche, Università di Napoli “Federico II”, and INFN, Sezione di Napoli, Napoli, Italy.
    Jesus, A. P.
    Centro de Fisica Nuclear da Universidade de Lisboa, Lisboa, Portugal.
    Junker, M.
    Laboratori Nazionali del Gran Sasso, INFN, Assergi (AQ), Italy.
    Limata, B.
    Dipartimento di Scienze Fisiche, Università di Napoli “Federico II”, and INFN, Sezione di Napoli, Napoli, Italy.
    Menegazzo, R.
    INFN, Sezione di Padova, via Marzolo 8, 35131, Padova, Italy; Laboratori Nazionali di Legnaro, INFN, Legnaro (PD), Italy.
    Prati, P.
    Dipartimento di Fisica, Università di Genova, and INFN, Genova, Italy.
    Roca, V.
    Dipartimento di Scienze Fisiche, Università di Napoli “Federico II”, and INFN, Sezione di Napoli, Napoli, Italy.
    Rogalla, D.
    Seconda Università di Napoli, Caserta, and INFN, Sezione di Napoli, Napoli, Italy.
    Rolfs, C.
    Institut für Experimentalphysik III, Ruhr-Universität Bochum, Bochum, Germany.
    Romano, M.
    Dipartimento di Scienze Fisiche, Università di Napoli “Federico II”, and INFN, Sezione di Napoli, Napoli, Italy.
    Rossi Alvarez, C.
    INFN, Sezione di Padova, via Marzolo 8, 35131, Padova, Italy.
    Schümann, F.
    Institut für Experimentalphysik III, Ruhr-Universität Bochum, Bochum, Germany.
    Somorjai, E.
    ATOMKI, Debrecen, Hungary.
    Straniero, O.
    Osservatorio Astronomico di Collurania, Teramo, and INFN, Sezione di Napoli, Napoli, Italy.
    Strieder, F.
    Institut für Experimentalphysik III, Ruhr-Universität Bochum, Bochum, Germany.
    Terrasi, F.
    Seconda Università di Napoli, Caserta, and INFN, Sezione di Napoli, Napoli, Italy.
    Trautvetter, H. P.
    Institut für Experimentalphysik III, Ruhr-Universität Bochum, Bochum, Germany.
    Vomiero, Alberto
    INFN Laboratori Nazionali di Legnaro.
    Feasibility of low-energy radiative-capture experiments at the LUNA underground accelerator facility2005Ingår i: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 24, nr 2, s. 313-319Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The LUNA (Laboratory Underground for Nuclear Astrophysics) facility has been designed to study nuclear reactions of astrophysical interest. It is located deep underground in the Gran Sasso National Laboratory, Italy. Two electrostatic accelerators, with 50 and 400 kV maximum voltage, in combination with solid and gas target setups allowed to measure the total cross-sections of the radiative-capture reactions 2H2H(p, γ) 3He3Heand 14N14N(p, γ) 15O15Owithin their relevant Gamow peaks. We report on the gamma background in the Gran Sasso laboratory measured by germanium and bismuth germanate detectors, with and without an incident proton beam. A method to localize the sources of beam-induced background using the Doppler shift of emitted gamma rays is presented. The feasibility of radiative-capture studies at energies of astrophysical interest is discussed for several experimental scenarios. © Società Italiana di Fisica/Springer-Verlag 2005.

  • 20.
    Benetti, Daniele
    et al.
    INRS Centre for Energy, Materials and Telecommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1S2, Canada.
    Cui, Daling
    INRS Centre for Energy, Materials and Telecommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1S2, Canada.
    Zhao, Haiguang
    INRS Centre for Energy, Materials and Telecommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1S2, Canada; The State Key Laboratory and College of Physics, Qingdao University, No. 308 Ningxia Road, Qingdao, 266071, P. R. China.
    Rosei, Federico
    INRS Centre for Energy, Materials and Telecommunications, 1650 Boulevard Lionel-Boulet, Varennes, Québec, J3X 1S2, Canada; Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 610054, P. R. China.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Direct Measurement of Electronic Band Structure in Single Quantum Dots of Metal Chalcogenide Composites2018Ingår i: Small (Weinheim an der Bergstrasse, Germany), ISSN 1613-6810, Vol. 14, nr 51, artikel-id 1801668Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Metal chalcogenide quantum dots (QDs) are among the most promising materials as light harvesters in all-inorganic systems for applications in solar cells and production of solar fuels. The electronic band structure of composite QDs formed by lead and cadmium chalcogenides directly grafted on highly oriented pyrolytic graphite surfaces through successive ionic layer absorption and reaction is investigated. Atomic force microscopy and Kelvin probe force microscopy (KPFM) are applied to investigate PbS, CdS, and PbS/CdS QD systems. The variation of the surface potential of individual QDs is measured, investigating the evolution of the electronic band structure as a function of QD size and composition. A shift of the Fermi level toward more negative values occurs when QD size is increased. The shift is more pronounced in CdS than in PbS, while the composite PbS/CdS exhibits an intermediate behavior. The calculated shift is in good agreement with the experiments. These results highlight the ability of KPFM to directly measure the electronic band structure in individual QDs of metal chalcogenide composites. This feature regulates charge dynamics in composite systems, thereby affecting device performance. This work provides valuable insights for applications in several fields, in which charge injection plays a major role.

  • 21.
    Benetti, Daniele
    et al.
    INRS Centre for Energy, Materials and Telecommunications.
    Dembele, Kadiatou Therese
    INRS Centre for Energy, Materials and Telecommunications.
    Benavides, Jaime
    Département de Génie Électrique, École de Technologie Supérieure, Montréal.
    Zhao, Haiguang
    INRS Centre for Energy, Materials and Telecommunications, CNR-INO SENSOR Lab.
    Cloutier, Sylvain
    Département de Génie Électrique, École de Technologie Supérieure, Montréal.
    Concina, Isabella
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Rosei, Federico
    INRS Centre for Energy, Materials and Telecommunications, Institute for Fundamental and Frontier Science University of Electronic 15 Science and Technology of China, Center for Self-Assembled Chemical Structures, McGill University.
    Functionalized multi-wall carbon nanotubes/TiO2 composites as efficient photoanodes for dye sensitized solar cells2016Ingår i: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 4, nr 16, s. 3555-3562Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report on the effects of incorporation of different concentrations of carboxyl group (COOH)-functionalized multi-wall carbon nanotubes (F-MWCNTs) into TiO2 active layers for dye-sensitized solar cells (DSSCs). Standard DSSCs with bare TiO2 exhibit a photo-conversion efficiency (PCE) of 6.05% and a short circuit current density (Jsc) of 13.3 mA cm−2. The presence of 2 wt% F-MWCNTs in the photoanodes increases the PCE up to 7.95% and Jsc up to 17.5 mA cm−2. The photoanodes were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy. The electrochemical behaviour of the solar cells was investigated by electrochemical impedance spectroscopy (EIS). We attribute the improved performances to the combined effect of increased dye loading and reduced charge recombination (as clarified by dye loading and EIS measurements), due to the conformal coverage of F-MWCNTs, which allows fast and efficient charge collection in operating solar cells. These results can help in improving the PCE in DSSCs in an elegant and straightforward way, minimizing the need of additional steps (e.g. pre- and post-treatment with TiCl4) for photoanode preparation.

  • 22.
    Benetti, Daniele
    et al.
    INRS Centre for Energy, Materials and Telecommunications, Varennes, Québec, Canada.
    Jokar, Efat
    Department of Applied Chemistry, Institute of Molecular Science and Center for Emergent Functional Matter Science, National Chiao Tung University, Hsinchu, Taiwan. Center for Emergent Functional Matter Science, National Chiao Tung University, Taiwan.
    Yu, Che-Hsun
    Department of Applied Chemistry, Institute of Molecular Science and Center for Emergent Functional Matter Science, National Chiao Tung University, Taiwan.
    Fathi, Amir
    Department of Applied Chemistry, Institute of Molecular Science and Center for Emergent Functional Matter Science, National Chiao Tung University, Taiwan.
    Zhao, Haiguang
    INRS Centre for Energy, Materials and Telecommunications, Varennes, Québec, Canada.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Wei-Guang Diau, Eric
    Department of Applied Chemistry, Institute of Molecular Science and Center for Emergent Functional Matter Science, National Chiao Tung University, Hsinchu, Taiwan. Center for Emergent Functional Matter Science, National Chiao Tung University, Taiwan.
    Rosei, Federico
    INRS Centre for Energy, Materials and Telecommunications, Varennes, Québec, Canada. Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, China.
    Hole-extraction and photostability enhancement in highly efficient inverted perovskite solar cells through carbon dot-based hybrid material2019Ingår i: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 62, s. 781-790Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report the effect of the integration of carbon dots (Cdots) in high-performance inverted planar-heterojunction (PHJ) perovskite solar cells (PSCs). We used Cdots to modify the hole-transport layer in planar PSC devices. By introducing Cdots on graphene oxide (GO) as hole-transporting layer, the efficiency of the PSC improved significantly from 14.7% in the case of bare GO to 16.2% of the best device with optimized Cdots content. When applying Cdots with an engineered absorption in the UV range as downshifting layer, the device performance was further improved, attaining a maximum PCE of 16.8% (+14%); the stability of the device was also enhanced of more than 20%. Kelvin probe force microscopy (KPFM) and cyclic voltammetry (CV) were employed to analyze the electronic band alignment at the interface between GO/Cdots and the perovskite film. Holes were extracted and transferred to the conductive substrate more efficiently in the presence of Cdots, thus delaying charge recombination. Photoluminescence (PL), transient PL decays and transient photovoltage (TPV) decays investigated the charge-transfer kinetics and proved the retardation of charge recombination. This work reveals an effective enhancement of the performance of planar PSCs by using Cdots/GO as hole transport material.

  • 23.
    Bhatti, Adeel Liaquat
    et al.
    Institute of Physics University of Sindh Jamshoro, 76080, Sindh Pakistan.
    Tahira, Aneela
    Dr. M.A Kazi Institute of Chemistry University of Sindh Jamshoro, 76080, Sindh Pakistan.
    Gradone, Alessandro
    Institute for Microelectronics and Microsystems, Italian National Research Council, Section of Bologna, Via Piero Gobetti 101, 40129, Bologna, Italy; Department of Chemistry “G.Ciamician”, University of Bologna, Via Selmi 2, 40126, Bologna, Italy.
    Mazzaro, Raffaello
    Institute for Microelectronics and Microsystems, Italian National Research Council, Section of Bologna, Via Piero Gobetti 101, 40129, Bologna, Italy; Department of Physics and Astronomy “A. Righi”, University of Bologna, Via Berti Pichat 6/2, 40127, Bologna, Italy.
    Morandi, Vittorio
    Institute for Microelectronics and Microsystems, Italian National Research Council, Section of Bologna, Via Piero Gobetti 101, 40129, Bologna, Italy.
    aftab, Umair
    Department of Metallurgy and Materials Engineering, Mehran University of Engineering and Technology, 7680 Jamshoro, Sindh Pakistan.
    Abro, Muhammad Ishaq
    Department of Metallurgy and Materials Engineering, Mehran University of Engineering and Technology, 7680 Jamshoro, Sindh Pakistan.
    Nafady, Ayman
    Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
    Qi, Kezhen
    Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang 110034, China.
    Infantes-Molina, Antonia
    Department of Inorgnic Chemistry, Crystallography and Mineralogy. (Unidad Asociada al ICP-CSIC), Faculty of Sciences, University of Malaga, Campus de Teatinos, 29071 Malaga, Spain..
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy.
    Ibupoto, Zafar Hussain
    Dr. M.A Kazi Institute of Chemistry University of Sindh Jamshoro, 76080, Sindh Pakistan.
    Nanostructured Co3O4 electrocatalyst for OER: The role of organic polyelectrolytes as soft templates2021Ingår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 398, artikel-id 139338Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Designing an efficient electrocatalyst for the oxygen evolution reaction (OER) in alkaline media is highly needed but very challenging task. Herein, we used organic polyelectrolytes such as (carboxymethyl cellulose) CMC and polyacrylamide polymers for the growth of Co3O4 nanostructures by aqueous chemical growth method. The morphology and composition studies were performed on scanning electron microscopy (SEM), energy dispersive X-ray (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) techniques. The structural properties and the surface chemistry of the Co3O4 electrocatalysts were correlated to the OER performance, and the enhancement mechanism with respect to pristine Co3O4 was observed to be specifically related to the polyelectrolyte templating role.

    Co3O4@CMC composites displayed reduced crystallite size, producing OER overpotential as low as 290 mV at 10 mAcm−2 in 1.0 KOH and Tafel slope of 71 mVdec−1, suggesting fast transfer of intermediates and electrons during water electrolysis. On the other hand, the use of polyacrylamide and its different templating mechanism resulted in similar crystallite size, but preferential exposed faces and larger surface vacancies content, as demonstrated by HR-TEM and XPS, respectively. Consistently, this material displays cutting-edge OER performance, such as overpotential of 260 mV at 10 mAcm−2 and a low Tafel slope of 63 mVdec−1. The proposed strategy for the preparation of Co3O4 nanostructures in the presence of CMC and polyacrylamide is facile, mass production, thus it could equally contributed towards the realization of hydrogen energy. Therefore, these nanostructures of Co3O4 can be regarded as an alternative and promising materials for the different electrochemical applications including fuel cells, metal air batteries, overall water electrolysis and other energy storage devices.

  • 24.
    Bianchi, S.
    et al.
    CNR IDASC SENSOR Lab.
    Comini, E.
    CNR IDASC SENSOR Lab.
    Ferroni, M.
    CNR IDASC SENSOR Lab.
    Faglia, G.
    CNR IDASC SENSOR Lab.
    Vomiero, Alberto
    University of Brescia, CNR-INFM SENSOR Laboratory.
    Sberveglieri, G.
    CNR IDASC SENSOR Lab.
    Indium oxide quasi-monodimensional low temperature gas sensor2006Ingår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 118, nr 1-2, s. 204-207Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have investigated the sensing properties of indium oxide nanostructures and tailored the deposition conditions in order to obtain nano-wires of indium oxide. We have comparatively tested the gas sensing properties of nano-wires with micrometric or even nanometric size. The micro-wires feature interesting gas sensitivity at room temperature, particularly in the case of nitrogen dioxide detection. The sensing performance is improved as the lateral dimension of the wire decreases. © 2006 Elsevier B.V. All rights reserved.

  • 25.
    Borgani, Riccardo
    et al.
    Nanostructure Physics, KTH Royal Institute of Technology, Stockholm, Sweden.
    Gilzad Kohan, Mojtaba
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Haviland, David B.
    Nanostructure Physics, KTH Royal Institute of Technology, Stockholm, Sweden.
    Fast Multifrequency Measurement of Nonlinear Conductance2019Ingår i: Physical Review Applied, E-ISSN 2331-7019, Vol. 11, nr 4, artikel-id 044062Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe a phase-coherent multifrequency lock-in measurement technique that uses the inverse Fourier transform to reconstruct the nonlinear current-voltage characteristic of a nanoscale junction. The method provides separation of the galvanic and displacement currents in the junction and easy cancellation of the parasitic displacement current from the measurement leads. These two features allow us to overcome traditional limitations imposed by the low conductance of the junction and the high capacitance of the leads, thus providing an increase in measurement speed of several orders of magnitude. We demonstrate the method in the context of conductive atomic force microscopy, acquiring current-voltage characteristics at every pixel while scanning at standard imaging speed.

  • 26.
    Bortoluzzi, Marco
    et al.
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia.
    Castro, Jesús
    Departamento de Química Inorgánica, Universidade de Vigo, Facultade de Química, Edificio de Ciencias Experimentais.
    Enrichi, Francesco
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Consorzio Interuniversitario Reattività Chimica e Catalisi (CIRCC) .
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Busato, Marta
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia.
    Huang, Weizhe
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia.
    Green-emitting manganese (II) complexes with phosphoramide and phenylphosphonic diamide ligands2018Ingår i: Inorganic Chemistry Communications, ISSN 1387-7003, E-ISSN 1879-0259, Vol. 92, s. 145-150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tetrahedral manganese(II) complexes having formulae [MnX2{O = PR(NMe2)2}2] (X = Br, I; R = NMe2, Ph) were isolated and characterized, and in the case of [MnBr2{O = PPh(NMe2)2}2] the structure was ascertained by means of single crystal X-ray diffraction. All the complexes showed intense green emission assigned to the Mn(II) 4T1(4G) → 6A1(6S) transition upon excitation with UV light, with photoluminescence lifetimes in the range 100–1000 μs. Bromo-complexes maintain their luminescence features once dispersed in polycaprolactone matrix.

  • 27.
    Bortoluzzi, Marco
    et al.
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia, Mestre, VE, Italy;Consorzio Interuniversitario Reattività Chimica e Catalisi (CIRCC), Bari, Italy.
    Castro, Jesús
    Departamento de Química Inorgánica, Universidade de Vigo, Facultade de Química, Edificio de Ciencias Experimentais, Galicia, Spain.
    Girotto, Matteo
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia, Mestre, VE, Italy.
    Enrichi, Francesco
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia, Mestre, VE, Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia, Mestre, VE, Italy.
    Luminescent copper(I) coordination polymer with 1-methyl-1H-benzotriazole, iodide and acetonitrile as ligands2019Ingår i: Inorganic Chemistry Communications, ISSN 1387-7003, E-ISSN 1879-0259, Vol. 102, s. 141-146Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Cu(I) coordination polymer [Cu33-I)3(μ-btzMe)(NCCH3)]n (btzMe = 1-methyl-1H-benzotriazole) was prepared and characterized by X-Ray diffraction. The compound showed strong green emission upon excitation with wavelengths below 475 nm, with lifetime of 47 μs. The emission was attributed to 3(X,M)LCT transition on the basis of experimental data and DFT calculations.

  • 28.
    Bortoluzzi, Marco
    et al.
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia, Italy. Consorzio Interuniversitario Reattività Chimica e Catalisi (CIRCC), Italy.
    Gobbo, Alberto
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia, Italy.
    Palù, Alberto
    Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia, Italy.
    Enrichi, Francesco
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia, Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca’ Foscari Venezia, Italy.
    Luminescent lanthanide complexes with phosphoramide and arylphosphonic diamide ligands2020Ingår i: Chemické zvesti, ISSN 0366-6352, E-ISSN 1336-9075, Vol. 74, nr 11, s. 3693-3704Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The sensitization of Eu(III) luminescence by the phosphoramide and arylphosphonic diamide ligands OP(NMe2)2Ind, OP(NMe2)2Cbz, OP(NMe2)2Ph, OP(NMe2)2(1-Naph) and OP(NMe2)2(2-Naph) (Ind = indol-1-yl; Ph = phenyl; Cbz = carbazol-9-yl; 1-Naph = naphtalen-1-yl; 2-Naph = naphtalen-2-yl) was verified by coordination to the [Eu(NO3)3] metal fragment. The emission spectra of the corresponding complexes showed only the 5D0 → 7FJ transitions of the metal centre, with the exception of the carbazolyl derivative. Some of the ligands were also able to sensitize Tb(III) luminescence, in agreement with the triplet state energies estimated from the phosphorescence spectra of the analogous Gd(III) nitrates. On the basis of the photoluminescence results achieved using nitrate as ancillary ligand, heptacoordinate Eu(III) complexes having general formula [Eu(β-dike)3L] (β-dike = dibenzoylmethanate, tenoyltrifluoroacetonate; L = phosphoramide or arylphosphomic diamide ligand) were prepared and characterized. All the complexes exhibited bright red emission upon excitation with near-UV and violet-blue light, with intrinsic quantum yields ranging between 18 and 36%.

  • 29.
    Boscarino, Diego
    et al.
    INFN Laboratori Nazionali di Legnaro.
    Vomiero, Alberto
    INFN Laboratori Nazionali di Legnaro.
    Mattei, Giovanni
    INFM Unit̀ di Ricerca di Padova.
    Quaranta, Alberto
    INFN Laboratori Nazionali di Legnaro.
    Mazzoldi, Paolo
    INFM Unit̀ di Ricerca di Padova.
    Mea, Gianantonio Della
    INFN Laboratori Nazionali di Legnaro.
    Deposition of silica-silver nanocomposites by magnetron cosputtering2005Ingår i: Journal of Vacuum Science & Technology B, ISSN 1071-1023, E-ISSN 1520-8567, Vol. 23, nr 1, s. 11-19Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Thin films have been grown on silicon and silica substrates by cosputtering of silica and silver in Ar, Ar+2.5% O2, and Ar+5% O2 gas mixtures. Rutherford backscattering spectrometry showed that the films have Ag atomic fractions xAg in the range of ∼1 to ∼10 at. %, and, by valence considerations, that the fraction of oxidized Ag in the films deposited in presence of oxygen is limited. Transmission electron microscopy images revealed the presence of Ag nanoclusters, with a mean size diameter not larger than 5 nm. The clusters are preferentially arranged along columns. It is suggested that the columns are regions with diameter in the nanometer range in which the density of the dielectric matrix is lower, thus favoring the formation of metal clusters. In presence of O2, the clusters were observed to have a more regular spherical shape. The optical absorption spectra of films grown in presence of O2 are distinguished from those grown in Ar by specific features, which are attributed to oxidation at the cluster surface. © 2005 American Vacuum Society.

  • 30.
    Botella, Pablo
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Enrichi, Francesco
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Venezia, Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Muñoz-Santiuste, Juan E.
    Departamento de Física, MALTA Consolider Team, Escuela Politécnica Superior, Universidad Carlos III de Madrid, Leganés, Spain.
    Garg, Alka B.
    High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai, India.
    Arvind, Ananthanarayanan
    Process Development Division, Bhabha Atomic Research Centre, Mumbai, India.
    Manjón, Francisco J.
    nstituto de Diseño para la Fabricación y Producción Automatizada, MALTA Consolider Team, Universitat Politècnica de València, València, Spain.
    Segura, Alfredo
    Departamento de Física Aplicada-ICMUV, Universidad de Valencia, MALTA Consolider Team, Edificio de Investigación, Burjassot, Spain.
    Errandonea, Daniel
    Departamento de Física Aplicada-ICMUV, Universidad de Valencia, MALTA Consolider Team, Edificio de Investigación, Burjassot, Spain.
    Investigation on the Luminescence Properties of InMO(M = V5+, Nb5+, Ta5+) Crystals Doped with Tb3+ or Yb3+ Rare Earth Ions2020Ingår i: ACS Omega, E-ISSN 2470-1343, Vol. 5, nr 5, s. 2148-2158Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We explore the potential of Tb- and Yb-doped InVO4, InTaO4, and InNbO4 for applications as phosphors for light-emitting sources. Doping below 0.2% barely change the crystal structure and Raman spectrum but provide optical excitation and emission properties in the visible and near-infrared (NIR) spectral regions. From optical measurements, the energy of the first/second direct band gaps was determined to be 3.7/4.1 eV in InVO4, 4.7/5.3 in InNbO4, and 5.6/6.1 eV in InTaO4. In the last two cases, these band gaps are larger than the fundamental band gap (being indirect gap materials), while for InVO4, a direct band gap semiconductor, the fundamental band gap is at 3.7 eV. As a consequence, this material shows a strong self-activated photoluminescence centered at 2.2 eV. The other two materials have a weak self-activated signal at 2.2 and 2.9 eV. We provide an explanation for the origin of these signals taking into account the analysis of the polyhedral coordination around the pentavalent cations (V, Nb, and Ta). Finally, the characteristic green (5D4 → 7FJ) and NIR (2F5/2 → 2F7/2) emissions of Tb3+ and Yb3+ have been analyzed and explained.

  • 31.
    Botella, Pablo
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Errandonea, D.
    Universidad de Valencia, Valencia, Spain.
    Garg, A.B.
    Bhabha Atomic Research Centre, Mumbai, India. Homi Bhabha National Institute, Mumbai, India.
    Rodriguez-Hernandez, P.
    Universidad de La Laguna, La Laguna, Spain.
    Muñoz, A.
    Departamento de Física, Instituto de Materiales y Nanotecnología, MALTA Consolider Team, Universidad de La Laguna, La Laguna, Spain.
    Achary, S.N
    Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    High-pressure characterization of the optical and electronic properties of InVO4, InNbO4, and InTaO42019Ingår i: SN Applied Sciences, ISSN 2523-3963, E-ISSN 2523-3971, Vol. 1, nr 5, artikel-id 389Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have studied the electronic properties at ambient pressure and under high pressure of InVO4, InNbO4, and InTaO4 powders, three candidate materials for hydrogen production by means of photocatalytic water splitting using solar energy. A combination of optical absorption and resistivity measurements and band structure calculations have allowed us to determine that these materials are wide band-gap semiconductors with a band-gap energy of 3.62(5), 3.63(5), and 3.79(5) eV for InVO4, InNbO4, and InTaO4, respectively. The last two compounds are indirect band-gap materials, and InVO4 is a direct band-gap material. The pressure dependence of the band-gap energy and the electrical resistivity have been determined too. In the three compounds, the band gap opens under compression until reaching a critical pressure, where a phase transition occurs. The structural transition triggers a band-gap collapse larger than 1.2 eV in the three materials, being the abrupt decrease in the band-gap energy related to an increase in the pentavalent cation coordination number. The phase transitions also cause changes in the electrical resistivity, which can be correlated with changes induced by pressure in the band structure. An explanation to the reported results is provided based upon ab initio calculations. The conclusions attained are of significance for technological applications of the studied oxides.

  • 32.
    Botella, Pablo
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    López Moreno, Sinhué
    Materiales Avanzados, Instituto Potosino de Investigacion Cientifica y Tecnologica AC, Camino a la presa de San Jose 2055, San Luis Potosi, San Luis Potosí, 78216, MEXICO.
    Errandonea, Daniel
    Department of Applied Physics, Universidad de Valencia, Dr Moliner 50, Bursasot (46100), Valencia, Burjassot, SPAIN.
    Manjon Herrera, Francisco Javier
    Departamento de Fisica Aplicada, Universitat Politecnica de Valencia, Escuela Tecnica Superior de Ingenieria del Disenyo, Cno.de Vera s/n, Valencia, Valencia, 46022, SPAIN.
    Sans, Juan Ángel
    Universitat Politecnica de Valencia, Departamento de Fisica Aplicada Escuela Tecnica Superior de Ingenieria del Disenyo Cno.de Vera s/n Valencia, Valencia, ES 46022 00-96-387-70-00 ex. 75255, Valencia, SPAIN.
    Vie, David
    Universitat de Valencia Instituto de Ciencia de los Materiales, Paterna, Comunitat Valenciana, SPAIN.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    High-pressure characterization of multifunctional CrVO42020Ingår i: Journal of Physics: Condensed Matter, ISSN 0953-8984, E-ISSN 1361-648X, Vol. 32, nr 38, artikel-id 385403Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The structural stability and physical properties of CrVO4 under compression were studied by X-ray diffraction, Raman spectroscopy, optical absorption, resistivity measurements, and ab initio calculations up to 10 GPa. High-pressure X-ray diffraction and Raman measurements show that CrVO4 undergoes a phase transition from the ambient pressure orthorhombic CrVO4-type structure (Cmcm space group, phase III) to the high-pressure monoclinic CrVO4-V phase, which is isomorphic to the wolframite structure. Such a phase transition (CrVO4-type → wolframite), driven by pressure, also was previously observed in indium vanadate. The crystal structure of both phases and the pressure dependence in unit-cell parameters, Raman-active modes, resistivity, and electronic band gap, is reported.  Vanadium atoms are sixth-fold coordinated in the wolframite phase, which is related to the collapse in the volume at the phase transition. Besides, we also observed drastic changes in the phonon spectrum, a drop of the band-gap, and a sharp decrease of resistivity. All the observed phenomena are explained with the help of first-principles calculations.

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  • 33.
    Braga, Antonio
    et al.
    Photovoltaic and Optoelectronic Devices Group.
    Giménez, Sixto
    Photovoltaic and Optoelectronic Devices Group.
    Concina, Isabella
    Department of Physics and Chemistry, INFM — University of Brescia.
    Vomiero, Alberto
    Department of Physics and Chemistry for Materials and Engineering and CNR-IDASC SENSOR Lab, Brescia University.
    Mora-Seró, Iván
    Photovoltaic and Optoelectronic Devices Group.
    Panchromatic sensitized solar cells based on metal sulfide quantum dots grown directly on nanostructured TiO2 electrodes2011Ingår i: Journal of Physical Chemistry Letters, Vol. 2, nr 5, s. 454-460Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The use of narrow band gap semiconductors such as PbS may expand the light absorption range to the near-infrared region in quantum-dot-sensitized solar cells (QDSCs), increasing the generated photocurrent. However, the application of PbS as a sensitizer in QDSCs causes some problems of stability and high recombination. Here, we show that the direct growth of a CdS coating layer on previously deposited PbS by the simple method of successive ionic layer adsorption and reaction (SILAR) minimizes these problems. A remarkable short-circuit current density for PbS/CdS QDSCs is demonstrated, ∼11 mA/cm2, compared to that of PbS QDSCs, with photocurrents lower than 4 mA/cm2, using polysulfide electrolyte in both cells. The cell efficiency reached a promising 2.21% under 1 sun of simulated irradiation (AM1.5G, 100 mW/cm2). Enhancement of the solar cell performance beyond the arithmetic addition of the efficiencies of the single constituents (PbS and CdS) is demonstrated for the nanocomposite PbS/CdS configuration. PbS dramatically increases the obtained photocurrents, and the CdS coating stabilizes the solar cell behavior. © 2011 American Chemical Society.

  • 34.
    Caciolli, A.
    et al.
    Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Padova, via Marzolo 8, 35131 Padova, Italy; Dipartimento di Scienze della Terra, Università di Siena, 53100 Siena; and Centro di GeoTecnologie CGT, 52027 San Giovanni Valdarno, Italy .
    Mazzocchi, C.
    Università degli Studi di Milano and INFN, Sezione di Milano, 20133 Milano, Italy.
    Capogrosso, V.
    Università degli Studi di Milano and INFN, Sezione di Milano, 20133 Milano, Italy.
    Bemmerer, D.
    Helmholtz–Zentrum Dresden–Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany.
    Broggini, C.
    Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Padova, via Marzolo 8, 35131 Padova, Italy.
    Corvisiero, P.
    Università di Genova and INFN Sezione di Genova, Genova, 16146 Genova, Italy.
    Costantini, H.
    Università di Genova and INFN Sezione di Genova, Genova, 16146 Genova, Italy.
    Elekes, Z.
    Institute of Nuclear Research (ATOMKI), 4026 Debrecen, Hungary.
    Formicola, A.
    INFN, Laboratori Nazionali del Gran Sasso (LNGS), 67010 Assergi (AQ), Italy.
    Fülöp, Zs
    Institute of Nuclear Research (ATOMKI), 4026 Debrecen, Hungary.
    Gervino, G.
    Dipartimento di Fisica Sperimentale, Università di Torino and INFN Sezione di Torino, 10125 Torino, Italy.
    Guglielmetti, A.
    Università degli Studi di Milano and INFN, Sezione di Milano, 20133 Milano, Italy.
    Gustavino, C.
    INFN, Laboratori Nazionali del Gran Sasso (LNGS), 67010 Assergi (AQ), Italy.
    Gyürky, Gy
    Institute of Nuclear Research (ATOMKI), 4026 Debrecen, Hungary.
    Imbriani, G.
    Dipartimento di Scienze Fisiche, Università di Napoli Federico II, and INFN Sezione di Napoli, 80126 Napoli, Italy.
    Junker, M.
    INFN, Laboratori Nazionali del Gran Sasso (LNGS), 67010 Assergi (AQ), Italy.
    Lemut, A.
    Università di Genova and INFN Sezione di Genova, Genova, 16146 Genova, Italy.
    Marta, M.
    Helmholtz–Zentrum Dresden–Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany.
    Menegazzo, R.
    Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Padova, via Marzolo 8, 35131 Padova, Italy.
    Palmerini, S.
    Dipartimento di Fisica, Università degli studi di Perugia and INFN, Sezione di Perugia, 06123 Perugia, Italy.
    Prati, P.
    Università di Genova and INFN Sezione di Genova, Genova, 16146 Genova, Italy.
    Roca, V.
    9 Dipartimento di Scienze Fisiche, Università di Napoli Federico II, and INFN Sezione di Napoli, 80126 Napoli, Italy.
    Rolfs, C.
    Institut für Experimentalphysik, Ruhr–Universität Bochum, 44780 Bochum, Germany.
    Alvarez, C. Rossi
    Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Padova, via Marzolo 8, 35131 Padova, Italy.
    Somorjai, E.
    Institute of Nuclear Research (ATOMKI), 4026 Debrecen, Hungary.
    Straniero, O.
    INAF – Osservatorio Astronomico di Collurania, 64100 Teramo, Italy.
    Strieder, F.
    Institut für Experimentalphysik, Ruhr–Universität Bochum, 44780 Bochum, Germany.
    Terrasi, F.
    Seconda Università di Napoli, 81100 Caserta; and INFN Sezione di Napoli, 80126 Napoli, Italy.
    Trautvetter, H. P.
    Institut für Experimentalphysik, Ruhr–Universität Bochum, 44780 Bochum, Germany.
    Vomiero, Alberto
    CNR-IDASC SENSOR Lab and Dipartimento di Chimica e Fisica per l'Ingegneria e per i Materiali.
    Revision of the 15N(p, γ)16O reaction rate and oxygen abundance in H-burning zones2011Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 533, artikel-id A66Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Context. The NO cycle takes place in the deepest layer of a H-burning core or shell, when the temperature exceeds T ≈ 30 × 106 K. The O depletion observed in some globular cluster giant stars, always associated with a Na enhancement, may be due to either a deep mixing during the red giant branch (RGB) phase of the star or to the pollution of the primordial gas by an early population of massive asymptotic giant branch (AGB) stars, whose chemical composition was modified by the hot bottom burning. In both cases, the NO cycle is responsible for the O depletion. Aims. The activation of this cycle depends on the rate of the 15N(p, γ)16O reaction. A precise evaluation of this reaction rate at temperatures as low as experienced in H-burning zones in stellar interiors is mandatory to understand the observed O abundances. Methods. We present a new measurement of the 15N(p, γ)16O reaction performed at LUNA covering for the first time the center of mass energy range 70-370 keV, which corresponds to stellar temperatures between 65 × 106 K and 780 × 106 K. This range includes the 15N(p, γ)16O Gamow-peak energy of explosive H-burning taking place in the external layer of a nova and the one of the hot bottom burning (HBB) nucleosynthesis occurring in massive AGB stars. Results. With the present data, we are also able to confirm the result of the previous R-matrix extrapolation. In particular, in the temperature range of astrophysical interest, the new rate is about a factor of 2 smaller than reported in the widely adopted compilation of reaction rates (NACRE or CF88) and the uncertainty is now reduced down to the 10% level. © 2011 ESO.

  • 35.
    Cailotto, Simone
    et al.
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy; CSGI − Italian Research Center for Colloids and Surface Science, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Firenze, Italy.
    Massari, Daniele
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy; CSGI − Italian Research Center for Colloids and Surface Science, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Firenze, Italy.
    Gigli, Matteo
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy; CSGI − Italian Research Center for Colloids and Surface Science, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Firenze, Italy.
    Campalani, Carlotta
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy.
    Bonini, Massimo
    CSGI − Italian Research Center for Colloids and Surface Science, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Firenze, Italy; Department of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Firenze, Italy.
    You, Shujie
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy.
    Selva, Maurizio
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy.
    Perosa, Alvise
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy.
    Crestini, Claudia
    Department of Molecular Sciences and Nanosystems, Ca’Foscari University of Venice, Via Torino 155, 30172 Venezia Mestre, Italy; CSGI − Italian Research Center for Colloids and Surface Science, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Firenze, Italy.
    N-Doped Carbon Dot Hydrogels from Brewing Waste for Photocatalytic Wastewater Treatment2022Ingår i: ACS Omega, E-ISSN 2470-1343, Vol. 7, nr 5, s. 4052-4061Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The brewery industry annually produces huge amounts of byproducts that represent an underutilized, yet valuable, source of biobased compounds. In this contribution, the two major beer wastes, that is, spent grains and spent yeasts, have been transformed into carbon dots (CDs) by a simple, scalable, and ecofriendly hydrothermal approach. The prepared CDs have been characterized from the chemical, morphological, and optical points of view, highlighting a high level of N-doping, because of the chemical composition of the starting material rich in proteins, photoluminescence emission centered at 420 nm, and lifetime in the range of 5.5–7.5 ns. With the aim of producing a reusable catalytic system for wastewater treatment, CDs have been entrapped into a polyvinyl alcohol matrix and tested for their dye removal ability. The results demonstrate that methylene blue can be efficiently adsorbed from water solutions into the composite hydrogel and subsequently fully degraded by UV irradiation.

  • 36.
    Cailotto, Simone
    et al.
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Mazzaro, Raffaello
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Enrichi, Francesco
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, Piazza del Viminale 1, 00184 Roma, Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Selva, Maurizio
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Cattaruzza, Elti
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Cristofori, Davide
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari Venezia, Via Torino 155, 30172 Venezia Mestre, Italy;Centro di microscopia elettronica “G. Stevanato”, Via Torino 155b, 30172 Venezia-Mestre, Italy.
    Amadio, Emanuele
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Perosa, Alvise
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Design of Carbon Dots for Metal-free Photoredox Catalysis2018Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, nr 47, s. 40560-40567Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The photoreduction potential of a set of four different carbon dots (CDs) was investigated. The CDs were synthesized by using two different preparation methods—hydrothermal and pyrolytic—and two sets of reagents—neat citric acid and citric acid doped with diethylenetriamine. The hydrothermal syntheses yielded amorphous CDs, which were either nondoped (a-CDs) or nitrogen-doped (a-N-CDs), whereas the pyrolytic treatment afforded graphitic CDs, either non-doped (g-CDs) or nitrogen-doped (g-N-CDs). The morphology, structure, and optical properties of four different types of CDs revealed significant differences depending on the synthetic pathway. The photocatalytic activities of the CDs were investigated as such, that is, in the absence of any other redox mediators, on the model photoreduction reaction of methyl viologen. The observed photocatalytic reaction rates: a-N-CDs ≥ g-CDs > a-CDs ≥ g-N-CDs were correlated with the presence/absence of fluorophores, to the graphitic core, and to quenching interactions between the two. The results indicate that nitrogen doping reverses the photoredox reactivity between amorphous and graphitic CDs and that amorphous N-doped CDs are the most photoredox active, a yet unknown fact that demonstrates the tunable potential of CDs for ad hoc applications.

  • 37.
    Campalani, Carlotta
    et al.
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari di Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Cattaruzza, Elti
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari di Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Zorzi, Sandro
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari di Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari di Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    You, Shujie
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Matthews, Lauren
    The European Synchrotron Radiation Facility, 38043 Grenoble CEDEX 9, France.
    Capron, Marie
    The European Synchrotron Radiation Facility, 38043 Grenoble CEDEX 9, France; Partnership for Soft Condensed Matter PSCM, ESRF The European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble CEDEX 9, France.
    Mondelli, Claudia
    CNR-IOM, Institut Laue Langevin, 71, Avenue des Martyrs, 38042 Grenoble CEDEX 9, France.
    Selva, Maurizio
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari di Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Perosa, Alvise
    Department of Molecular Sciences and Nanosystems, Università Ca’ Foscari di Venezia, Via Torino 155, 30172 Venezia Mestre, Italy.
    Biobased Carbon Dots: From Fish Scales to Photocatalysis2021Ingår i: Nanomaterials, E-ISSN 2079-4991, Vol. 11, nr 2, artikel-id 524Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The synthesis, characterization and photoreduction ability of a new class of carbon dots made from fish scales is here described. Fish scales are a waste material that contains mainly chitin, one of the most abundant natural biopolymers, and collagen. These components make the scales rich, not only in carbon, hydrogen and oxygen, but also in nitrogen. These self-nitrogen-doped carbonaceous nanostructured photocatalyst were synthesized from fish scales by a hydrothermal method in the absence of any other reagents. The morphology, structure and optical properties of these materials were investigated. Their photocatalytic activity was compared with the one of conventional nitrogen-doped carbon dots made from citric acid and diethylenetriamine in the photoreduction reaction of methyl viologen.

  • 38.
    Carturan, S.
    et al.
    University of Padova.
    Quaranta, A.
    University of Trento, Department of Materials Engineering and Industrial Technologies.
    Bonafini, M.
    Istituto Nazionale di Fisica Nucleare (INFN).
    Vomiero, Alberto
    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro.
    Maggioni, G.
    University of Padova.
    Mattei, G.
    De Julián Fernández, C.
    Bersani, M.
    Mazzoldi, P.
    Della Mea, G.
    University of Trento, Department of Materials Engineering and Industrial Technologies.
    Formation of silver nanoclusters in transparent polyimides by Ag-K ion-exchange process2007Ingår i: European Physical Journal D: Atomic, Molecular and Optical Physics, ISSN 1434-6060, E-ISSN 1434-6079, Vol. 42, nr 2, s. 243-251Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Silver nanoclusters embedded in two transparent fluorinated polyimides, 4,4'-hexafluoroisopropylidene diphthalic anhydride - 2,3,5,6-tetramethyl paraphenylene diamine (6FDA-DAD) and 3,3',4,4' - biphenyltetracarboxylic acid dianhydride - 1,1-bis(4-aminophenyl)-1-phenyl-2,2,2-trifluoroethane (BPDA-3F), have been produced by surface modification with KOH aqueous solution followed by K-assisted Ag doping and thermal reduction in hydrogen atmosphere. The reaction rate of the nucleophilic hydrolysis in KOH, studied by Fourier transform infrared spectroscopy (FT-IR) and Rutherford backscattering spectrometry (RBS), depends on the polyimide chemical structure. After ion-exchange in AgNO 3 solution and subsequent annealing, the polyimide structure recovery was monitored by FT-IR whereas the characteristic surface plasmon absorption band of silver nanoparticles was evidenced by optical absorption measurements. The structure of silver nanoclusters as related to size and size distribution in the different polyimide matrices was thoroughly investigated by Transmission electron microscopy (TEM) and X-ray diffraction (XRD). The collected data evidenced a uniform distribution of Ag clusters of nanometric size after thermal treatment at 300 °C in both polyimides. For the same ion-exchange treatment parameters and annealing temperature, XRD analyses evidenced the presence of crystallites with similar sizes. © EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2007.

  • 39. Carturan, S.
    et al.
    Quaranta, A.
    Laboratori Nazionali di Legnaro.
    Vomiero, Alberto
    Department of Physics, University of Padova.
    Bonafini, M.
    Department of Engineering Materials, Department of Mechanical Engineering, Linköping University.
    Maggioni, G.
    Della Mea, G.
    Laboratori Nazionali di Legnaro.
    Polyimide-based scintillators studied by ion beam induced luminescence2005Ingår i: IEEE Transactions on Nuclear Science, ISSN 0018-9499, E-ISSN 1558-1578, Vol. 52, nr 3 II, s. 748-751Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    New organic scintillators for ionizing radiation sensors are synthesized by dispersing dye molecules into chemically imidized polyimide hosts in order to obtain detection systems with improved radiation resistance with respect to the traditional polyvinyltoluene-based materials. Nile red (NR) and rhodamine B (RB) are dispersed at different concentrations in polyimides derived from the following monomers: 6FDA-DAD, 6FDA-DAB, and BPDA-3F. Scintillating thin films are produced by the spin coating technique. Scintillation tests are performed both on pure polyimides and on binary systems by means of ion beam induced luminescence (IBIL), in which the emission spectrum is collected during the irradiation of the films with a 4He+ beam. From the intensity and the degradation rate of the IBIL signal during irradiation, the scintillation efficiency with respect to NE102 and the radiation hardness of the produced films are calculated. © 2005 IEEE.

  • 40. Carturan, S.
    et al.
    Quaranta, A.
    Laboratori Nazionali di Legnaro.
    Vomiero, Alberto
    INFN Laboratori Nazionali di Legnaro.
    Bonafini, M.
    Laboratori Nazionali di Legnaro.
    Maggioni, G.
    Della Mea, G.
    Laboratori Nazionali di Legnaro.
    Polyimide-based scintillators studied by ion beam induced luminescence2004Ingår i: IEEE Nuclear Science Symposium Conference Record, ISSN 1095-7863, Vol. 2, s. 869-873Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    New organic scintillators for ionizing radiation sensors are synthesized by dispersing dye molecules into chemically imidized polyimide hosts in order to obtain detection systems with improved radiation resistance with respect to the traditional polyvinyltoluene based materials. Nile Red and Rhodamine B are dispersed at different concentrations in polyimides derived from the following monomers 6FDA-DAD, 6FDA-DAB and BPDA-3F. Scintillating thin films are produced by the spin coating technique. Scintillation tests are performed both on pure polyimides and on binary systems by means of Ion Beam Induced Luminescence (IBIL), in which the emission spectrum is collected during the irradiation of the films with a 4He+ beam. From the intensity and the degradation rate of the IBIL signal during irradiation, the scintillation efficiency with respect to NE102 and the radiation hardness of the produced films are calculated. © 2004 IEEE.

  • 41.
    Comini, E.
    et al.
    CNR IDASC SENSOR Lab.
    Baratto, C.
    CNR IDASC SENSOR Lab.
    Faglia, G.
    CNR IDASC SENSOR Lab.
    Ferroni, M.
    CNR IDASC SENSOR Lab.
    Vomiero, Alberto
    CNR-INFM SENSOR Laboratory.
    Sberveglieri, G.
    CNR IDASC SENSOR Lab.
    Quasi-one dimensional metal oxide semiconductors: Preparation, characterization and application as chemical sensors2009Ingår i: Progress in Materials Science, ISSN 0079-6425, E-ISSN 1873-2208, Vol. 54, nr 1, s. 1-67Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The continuous evolution of nanotechnology in these years led to the production of quasi-one dimensional (Q1D) structures in a variety of morphologies such as nanowires, core-shell nanowires, nanotubes, nanobelts, hierarchical structures, nanorods, nanorings. In particular, metal oxides (MOX) are attracting an increasing interest for both fundamental and applied science. MOX Q1D are crystalline structures with well-defined chemical composition, surface terminations, free from dislocation and other extended defects. In addition, nanowires may exhibit physical properties which are significantly different from their coarse-grained polycrystalline counterpart because of their nanosized dimensions. Surface effects dominate due to the increase of their specific surface, which leads to the enhancement of the surface related properties, such as catalytic activity or surface adsorption: key properties for superior chemical sensors production. High degree of crystallinity and atomic sharp terminations make nanowires very promising for the development of a new generation of gas sensors reducing instabilities, typical in polycrystalline systems, associated with grain coalescence and drift in electrical properties. These sensitive nanocrystals may be used as resistors, and in FET based or optical based gas sensors. This article presents an up-to-date review of Q1D metal oxide materials research for gas sensors application, due to the great research effort in the field it could not cover all the interesting works reported, the ones that, according to the authors, are going to contribute to this field's further development were selected and described. © 2008 Elsevier Ltd. All rights reserved.

  • 42.
    Comini, E.
    et al.
    INFM-CNR Sensor Lab.
    Bianchi, S.
    INFM-CNR Sensor Lab.
    Faglia, G.
    INFM-CNR Sensor Lab.
    Ferroni, M.
    INFM-CNR Sensor Lab.
    Vomiero, Alberto
    INFM-CNR Sensor Lab.
    Sberveglieri, G.
    INFM-CNR Sensor Lab.
    Functional nanowires of tin oxide2007Ingår i: Applied Physics A: Materials Science & Processing, ISSN 0947-8396, E-ISSN 1432-0630, Vol. 89, nr 1, s. 73-76Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quasi-one-dimensional nanostructures of tin oxide were produced in controlled conditions through condensation from the vapor phase. The preparation was assisted by noble metal catalysts and uniform single-crystalline nanowires were produced. The nucleation of nanowires was achieved at 470 °C, owing to the vapor-liquid-solid growth mechanism activated by the catalytic Pt clusters. The peculiar microstructural properties of these semiconducting metal oxide nanostructures will be summarized. The high aspect ratio and the high degree of crystallinity achieved for the nanowires foresee their functional exploitation. © 2007 Springer-Verlag.

  • 43.
    Comini, E.
    et al.
    CNR IDASC SENSOR Lab.
    Vomiero, Alberto
    INFN Laboratori Nazionali di Legnaro.
    Faglia, G.
    CNR IDASC SENSOR Lab.
    Della Mea, G.
    INFN.
    Sberveglieri, G.
    CNR IDASC SENSOR Lab.
    Influence of iron addition on ethanol and CO sensing properties of tin oxide prepared with the RGTO technique2006Ingår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 115, nr 2, s. 561-566Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Effects of iron introduction in RGTO prepared tin oxide gas sensors are presented. The films were deposited by sputtering from a tin target with the introduction of an adjustable number or iron inset. Iron content was varied in the range 0-7%. The thin films are investigated by the volt-amperometric technique for electrical and gas-sensing properties. The layers are capable of sensing CO and ethanol, no evidence of surface poisoning is detected, and recovery of the resistance is complete. The response of the sensors is stable and reproducible at all operating temperatures tested (200-500 °C) during 3 months of operation. © 2005 Elsevier B.V. All rights reserved.

  • 44.
    Comini, Elisabetta
    et al.
    CNR IDASC SENSOR Lab.
    Baratto, Camilla
    CNR IDASC SENSOR Lab.
    Concina, Isabella
    CNR IDASC SENSOR Lab.
    Faglia, Guido
    CNR IDASC SENSOR Lab.
    Falasconi, Matteo
    CNR IDASC SENSOR Lab.
    Ferroni, Matteo
    CNR IDASC SENSOR Lab.
    Galstyan, Vardan
    CNR IDASC SENSOR Lab.
    Gobbi, Emanuela
    CNR IDASC SENSOR Lab.
    Ponzoni, Andrea
    CNR IDASC SENSOR Lab.
    Vomiero, Alberto
    SENSOR Lab, Department of Information Engineering, University of Brescia.
    Zappa, Dario
    CNR IDASC SENSOR Lab.
    Sberveglieri, Veronica
    CNR IDASC SENSOR Lab.
    Sberveglieri, Giorgio
    CNR IDASC SENSOR Lab.
    Metal oxide nanoscience and nanotechnology for chemical sensors2013Ingår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 179, s. 3-20Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper focuses on the capabilities and development prospects of nanostructured metal oxides (MOX) representing the most versatile and richest class of materials in terms of electronic structure and structural, chemical, and physical properties. MOX nano-materials with controlled composition, surface terminations, and crystalline structures to be used as chemical sensors as a new area in analytical chemistry and instrument engineering are discussed. Their principles of operation, and basic characteristics are outlined and main applications of MOX sensor technology are presented. © 2012 Elsevier B.V. All rights reserved.

  • 45.
    Comini, Elisabetta
    et al.
    INFM-CNR Sensor Lab.
    Baratto, Camilla
    INFM-CNR Sensor Lab.
    Faglia, Guido
    INFM-CNR Sensor Lab.
    Ferroni, Matteo
    INFM-CNR Sensor Lab.
    Vomiero, Alberto
    University of Brescia, CNR-INFM SENSOR Laboratory.
    Sberveglieri, Giorgio
    INFM-CNR Sensor Lab.
    Highly sensitive single crystalline metal oxide nanowires gas sensors2006Ingår i: Proceedings of the 2006 Conference on Optoelectronic and Microelectronic Materials and Devices: 6-8 December 2006, Perth, Australia., Piscataway, NJ: IEEE Communications Society, 2006, s. 315-320, artikel-id 4429946Konferensbidrag (Refereegranskat)
    Abstract [en]

    Interest in nanowires of metal oxide oxides has been exponentially growing in the last years, due to the attracting potential of application in electronic, optical and sensor field. We have focused our attention on the sensing properties of semiconducting nanowires as conductometric and optical gas sensors. Single crystal nanostructures In2O3, SnO 2, and ZnO were synthesized to explore and study their capability in form of multi-nanowires sensors. © 2006 IEEE.

  • 46.
    Comini, Elisabetta
    et al.
    CNR IDASC SENSOR Lab.
    Faglia, Guido
    CNR IDASC SENSOR Lab.
    Ferroni, Matteo
    CNR IDASC SENSOR Lab.
    Ponzoni, Andrea
    CNR IDASC SENSOR Lab.
    Vomiero, Alberto
    INFM-CNR Sensor Lab.
    Sberveglieri, Giorgio
    CNR IDASC SENSOR Lab.
    Metal oxide nanowires: Preparation and application in gas sensing2009Ingår i: Journal of Molecular Catalysis A: Chemical, ISSN 1381-1169, E-ISSN 1873-314X, Vol. 305, nr 1-2, s. 170-177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quasi one-dimensional nanowires of metal oxides are promising for the development of nano-devices. Sn, In, and Zn oxides were produced in form of single-crystalline nanowires through condensation from vapor phase. Furthermore longitudinal and radial heterostructures have been prepared. Nanowires growth occurs in controlled condition and allows the exploitation of size reduction effects on the electrical response to gases. Preparation, microstructural, morphological and electrical characterizations of nanowires are presented and the peculiarities of these innovative structures are highlighted. © 2009 Elsevier B.V. All rights reserved.

  • 47.
    Comini, Elisabetta
    et al.
    INFM-CNR Sensor Lab.
    Ferroni, Matteo
    INFM-CNR Sensor Lab.
    Guidi, Vincenzo
    INFM-CNR Sensor Lab.
    Vomiero, Alberto
    INFN - Legnaro National Laboratories.
    Merli, Pier Giorgio
    CNR.
    Morandi, Vittorio
    CNR.
    Sacerdoti, Michele
    Dipartimento di Scienze della Terra, via Laterina 8, 53100 Siena.
    Mea, Gianantonio Della
    INFN - Legnaro National Laboratories.
    Sberveglieri, Giorgio
    INFM-CNR Sensor Lab.
    Effects of Ta/Nb-doping on titania-based thin films for gas-sensing2005Ingår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 108, nr 1-2 SPEC. ISS., s. 21-28Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Thin films of titania with the addition of niobium and tantalum have been achieved by reactive sputtering process. Structural and morphological studies have been carried out by means of XRD, RBS, TEM and AFM in order to correlate the microstructural features to the sensing performance of the layers. The films proved sensitive to ethanol and carbon monoxide and ammonia. In the case of niobium addition, it was shown that annealing temperature and niobium content strongly influence the gas response of the films converting a n-type response, which is typical of pure TiO2 and of most of metal-oxide sensors, to a p-type response; this peculiarity is crucial for the discrimination of different gases. In the case of tantalum addition, the annealing treatment at 800 °C led only to a phase transformation that reduced the sensing performance of the layer. High sensitivity to CO is achieved with anatase or mixed anatase and rutile phases, while the rutile phase only exhibit a low gas sensitivity. © 2005 Elsevier B.V. All rights reserved.

  • 48.
    Concina, Isabella
    et al.
    CNR IDASC SENSOR Lab, Chemistry and Physics Department, University of Brescia, 25133 Brescia, Via Valotti 9, Italy.
    Frison, Enrico
    Dipartimento di Scienze Chimiche, ITM-CNR (Sezione di Padova), University of Padova, 35131 Padova, Via Marzolo 1, Italy.
    Braga, Antonio
    CNR IDASC SENSOR Lab, Chemistry and Physics Department, University of Brescia, 25133 Brescia, Via Valotti 9, Italy.
    Silvestrini, Simone
    Dipartimento di Scienze Chimiche, ITM-CNR (Sezione di Padova), University of Padova, 35131 Padova, Via Marzolo 1, Italy.
    Maggini, Michele
    Dipartimento di Scienze Chimiche, ITM-CNR (Sezione di Padova), University of Padova, 35131 Padova, Via Marzolo 1, Italy.
    Sberveglieri, Giorgio
    CNR IDASC SENSOR Lab, Chemistry and Physics Department, University of Brescia, 25133 Brescia, Via Valotti 9, Italy.
    Vomiero, Alberto
    CNR IDASC SENSOR Lab, Chemistry and Physics Department, University of Brescia, 25133 Brescia, Via Valotti 9, Italy.
    Carofiglio, Tommaso
    Dipartimento di Scienze Chimiche, ITM-CNR (Sezione di Padova), University of Padova, 35131 Padova, Via Marzolo 1, Italy.
    On-line monitoring and active control of dye uptake in dye-sensitised solar cells2011Ingår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 47, nr 42, s. 11656-11658Artikel i tidskrift (Refereegranskat)
  • 49.
    Concina, Isabella
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Ibupoto, Zafar Hussain
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Dr. M. A. Kazi Institute of Chemistry University of Sindh Jamshoro, Sindh, Pakistan.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Semiconducting metal oxide nanostructures for water splitting and photovoltaics2017Ingår i: Advanced Energy Materials, ISSN 1614-6832, E-ISSN 1614-6840, Vol. 7, nr 23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Metal oxide (MOx) semiconducting nanostructures hold the potential for playing a critical role in the development of a new platform for renewable energies, including energy conversion and storage through photovoltaic effect, solar fuels, and water splitting. Earth-abundant MOx nanostructures can be prepared through simple and scalable routes and integrated in operating devices, which enable exploitation of their outstanding optical, electronic, and catalytic properties. In this review, the latest research results in this field are illustrated, highlighting the versatility of MOx nanostructures in meeting the stringent requirements to boost the efficiency of different systems. The functional properties inherently correlate to the morphology and the crystalline habit of MOx, which in most of the cases are organized in complex heterostructures. Tailoring the assembly of heterojunctions and their electronic band structure, the catalytic surface properties and the charge transport through complex networks represent the main challenge for the transition of MOx from the research to the real-life in the field of energy conversion and storage.

  • 50.
    Concina, Isabella
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Ibupoto, Zafar
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Kazi Institute of Chemistry University of Sindh Jamshoro.
    Vomiero, Alberto
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Electrochemical Water Splitting: Semiconducting Metal Oxide Nanostructures for Water Splitting and Photovoltaics2017Ingår i: Advanced Energy Materials, ISSN 1614-6832, E-ISSN 1614-6840, Vol. 7, nr 23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Semiconducting metal oxide nanostructures represent an appealing class of materials to be applied as efficient electrodes in electrochemical and photoelectrochemical water splitting and in photovoltaics. In article number 1700706, Isabella Concina, Zafar Hussain Ibupoto, and Alberto Vomiero review the latest achievements in the field, illustrating how the structural and functional properties of metal oxides and metal oxide composites can be optimized for targeted applications.

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