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  • 1.
    Bhowmick, Sourav
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Filippov, Andrei
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Khan, Inayat Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Physical and electrochemical properties of new structurally flexible imidazolium phosphate ionic liquids2022Ingår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 24, nr 38, s. 23289-23300Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    New structurally flexible 1-methyl- and 1,2-dimethyl-imidazolium phosphate ionic liquids (ILs) bearing oligoethers have been synthesized and thoroughly characterized. These novel ILs revealed high thermal stabilities, low glass transitions, high conductivity and wide electrochemical stability windows up to 6 V. Both anions and cations of 1-methyl-imidazolium ILs diffuse faster than the ions of 1,2-dimethyl-imidazolium ILs, as determined by pulsed field gradient nuclear magnetic resonance (PFG-NMR). The 1-methyl-imidazolium phosphate ILs showed relatively higher ionic conductivities and ion diffusivity as compare with the 1,2-dimethyl-imidazolium phosphate ILs. As expected, the diffusivity of all the anions and cations increases with an increase in the temperature. The 1-methyl-imidazolium phosphate ILs formed hydrogen bonding with the phosphate anions, the strength of which is decreased with increasing temperature, as confirmed by variable temperature 1H and 31P NMR spectroscopy. One of the representative IL, [EmDMIm][DEEP], presented a promising performance at elevated temperatures as an electrolyte in a supercapacitor composed of multiwall carbon nanotubes and activated charcoal (MWCNTs/AC) composite electrodes.

  • 2.
    Gnezdilov, Oleg I.
    et al.
    Institute of Physics, Kazan Federal University, 420008 Kazan, Russia.
    Filippov, Andrei
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Medical and Biological Physics, Kazan Medical University, 420012, Kazan, Russia.
    Khan, Inayat Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Translational and reorientational dynamics of ionic liquid-based fluorine-free lithium-ion battery electrolytes2022Ingår i: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 345, artikel-id 117001Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The translational as well as reorientational mobilities of fluorine-free electrolytes prepared by mixing lithium furan-2-carboxylate Li(FuA) salt with tetra(n-butyl)phosphonium furan-2-carboxylate (P4444)(FuA) ionic liquid are thoroughly investigated. The diffusivity of ions and T1 relaxation of protons belonging to various chemical groups of (P4444)+ and (FuA) ions and the Li+ ion present in these electrolytes are measured as a function of lithium salt concentration and temperature. The temperature dependence of correlation time for reorientational mobility of various chemical groups of (P4444)+ and (FuA) ions and the Li+ ion are estimated and used in calculations temperature dependence of the corresponding reorientational rates. It is shown that an increase in the concentration of lithium salt leads to a decrease in both the diffusion coefficients and the reorientation rates for all the chemical groups in concerted way. Activation energy of the reorientational rates for different chemical groups of the organic ions and the Li+ are discussed in details.

  • 3.
    Hameed, Arslan
    et al.
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Batool, Mariam
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Iqbal, Waheed
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Abbas, Saghir
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan; Department of Biological Sciences, National University of Medical Sciences, Rawalpindi, Pakistan.
    Imran, Muhammad
    Department of Chemistry, Faculty of Sciences, King Khalid University, Abha, Saudi Arabia.
    Khan, Inayat
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Nadeem, Muhammad Arif
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    ZIF-12/Fe-Cu LDH Composite as a High Performance Electrocatalyst for Water Oxidation2021Ingår i: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 9, artikel-id 686969Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Layered double hydroxides (LDH) are being used as electrocatalysts for oxygen evolution reactions (OERs). However, low current densities limit their practical applications. Herein, we report a facile and economic synthesis of an iron-copper based LDH integrated with a cobalt-based metal-organic framework (ZIF-12) to form LDH-ZIF-12 composite (1) through a co-precipitation method. The as-synthesized composite 1 requires a low overpotential of 337 mV to achieve a catalytic current density of 10 mA cm−2 with a Tafel slope of 89 mV dec−1. Tafel analysis further demonstrates that 1 exhibits a slope of 89 mV dec−1 which is much lower than the slope of 284 mV dec−1 for LDH and 172 mV dec−1 for ZIF-12. The slope value of 1 is also lower than previously reported electrocatalysts, including Ni-Co LDH (113 mV dec−1) and Zn-Co LDH nanosheets (101 mV dec−1), under similar conditions. Controlled potential electrolysis and stability test experiments show the potential application of 1 as a heterogeneous electrocatalyst for water oxidation.

  • 4.
    Khan, Inayat Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Gnezdilov, Oleg I.
    Institute of Physics, Kazan Federal University, 420008 Kazan, Russia.
    Wang, Yong-Lei
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
    Filippov, Andrei
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Medical and Biological Physics, Kazan Medical University, 420012, Kazan, Russia.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Effect of Aromaticity in Anion on the Cation–Anion Interactions and Ionic Mobility in Fluorine-Free Ionic Liquids2020Ingår i: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 124, nr 52, s. 11962-11973Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ionic liquids (ILs) composed of tetra(n-butyl)phosphonium [P4444]+ and tetra(n-butyl)ammonium [N4444]+ cations paired with 2-furoate [FuA], tetrahydo-2-furoate [HFuA], and thiophene-2-carboxylate [TpA] anions are prepared to investigate the effects of electron delocalization in anion and the mutual interactions between cations and anions on their physical and electrochemical properties. The [P4444]+ cations-based ILs are found to be liquids, while the [N4444]+ cations-based ILs are semi-solids at room temperature. Thermogravimetric analysis revealed higher decomposition temperatures and differential scanning calorimetry analysis showed lower glass transition temperatures for phosphonium-based ILs than the ammonium-based counterparts. The ILs are arranged in the decreasing order of their ionic conductivities as [P4444][HFuA] (0.069 mS cm–1) > [P4444][FuA] (0.032 mS cm–1) > [P4444][TpA] (0.028 mS cm–1) at 20 °C. The oxidative limit of the ILs followed the sequence of [FuA]> [TpA]> [HFuA], as measured by linear sweep voltammetry. This order can be attributed to the electrons’ delocalization in [FuA] and in [TpA] aromatic anions, which has enhanced the oxidative limit potentials and the overall electrochemical stabilities.

  • 5.
    Khan, Inayat Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Ivanovich Gnezdilov, Oleg
    Institute of Physics, Kazan Federal University, 420008 Kazan, Russia.
    Filippov, Andrei
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Medical and Biological Physics, Kazan State Medical University, 420012 Kazan, Russia.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Ion Transport and Electrochemical Properties of Fluorine-Free Lithium-Ion Battery Electrolytes Derived from Biomass2021Ingår i: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 9, nr 23, s. 7769-7780Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Unlike conventional electrolytes, ionic liquid (IL)-based electrolytes offer higher thermal stability, acceptable ionic conductivity, and a higher electrochemical stability window (ESW), which are indispensable for the proper functioning of Li-ion batteries. In this study, fluorine-free electrolytes are prepared by mixing the lithium furan-2-carboxylate [Li(FuA)] salt with the tetra(n-butyl)phosphonium furan-2-carboxylate [(P4444)(FuA)] IL in different molar ratios. The anion of these electrolytes is produced from biomass and agricultural waste on a large scale and, therefore, this study is a step ahead toward the development of renewable electrolytes for batteries. The electrolytes are found to have Tonset higher than 568 K and acceptable ionic conductivities in a wide temperature range. The pulsed field gradient nuclear magnetic resonance (PFG-NMR) analysis has confirmed that the (FuA) anion diffuses faster than the (P4444)+ cation in the neat (P4444)(FuA) IL; however, the anion diffusion becomes slower than cation diffusion by doping Li salt. The Li+ ion interacts strongly with the carboxylate functionality in the (FuA) anion and diffuses slower than other ions over the whole studied temperature range. The interaction of the Li+ ion with the carboxylate group is also confirmed by 7Li NMR and Fourier transform infrared (FTIR) spectroscopy. The transference number of the Li+ ion is increased with increasing Li salt concentration. Linear sweep voltammetry (LSV) suggests lithium underpotential deposition and bulk reduction at temperatures above 313 K.

  • 6.
    Khan, Inayat Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Khan, Luqman
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Khan, Syed Ishtiaq
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Badshah, Amin
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Shape-control synthesis of PdCu nanoparticles with excellent catalytic activities for direct alcohol fuel cells application2020Ingår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 349, artikel-id 136381Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this article, we described a simple method of PdCu nanoparticles (NPs) synthesis in different morphologies at 120 °C using polyvinylpyrrolidone (PVP) capping agent and ethylene glycol (EG) solvent. Form instrumental characterization it is find out that PdCu NPs are prepared in different morphologies by varying the Pd:Cu weight percent (wt.%) ratios. Nanospheres (NS) are obtained in the absence of Cu, sphere-like NPs having Pd3Cu1 composition are obtained at 3:1 wt.% ratio, cubic NPs having Pd1Cu1 composition are obtained at 1:1 wt.% ratio and cube-like NPs having Pd1Cu3 composition are obtained at 1:3 wt.% ratio. The metals wt.% ratio not only controlled the morphology, but also affected the catalytic activity toward methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR) in alkaline media. The PdCu catalyst, in 1:1 wt.% ratio, have demonstrated high specific and mass activities toward MOR (18.07 mA cm−2 and 11.15 A mgPd−1) and EOR (10.24 mA cm−2 and 6.32 A mgPd−1) in alkaline media. Excellent catalytic activity and long-term stability of Pd1Cu1 toward both MOR and EOR is attributed to its stable cubic morphology, composition and synergetic effect, high electrochemical active surface area (ECSA) and PdO reduction at more negative potential. In comparison to the literature, the cubic-PdCu is one of the best electorcatalyst toward MOR and EOR. The cubic-PdCu NPs as anode have potential application in direct alcohol fuel cells owing to their excellent electrochemical performance, stability and cost effectiveness.

  • 7.
    Khan, Inayat Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Fluorine-Free Ionic Liquid-Based Electrolyte for Supercapacitors Operating at Elevated Temperatures2020Ingår i: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 8, nr 27, s. 10212-10221Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We synthesized tetra(n-butyl)phosphonium furoate [P4444][FuA] ionic liquid (IL) by the reaction of tetra(n-butyl)phosphonium hydroxide and 2-furoic acid using water as a solvent at room temperature. The thermal stability and phase behavior of the IL are investigated through thermogravimetry (TGA) and differential scanning calorimetry (DSC), while the ionic conductivity measurement is carried out using impedance spectroscopy. Hybrid carbon-based material composed of multi walled carbon nanotubes (MWCNTs) and activated charcoal is fabricated and used as electrodes. The effect of potential scan rate, temperature and voltage on the electrochemical performance of the capacitor is thoroughly investigated through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The results showed that the internal resistance and specific capacitance are highly dependent on the temperature and voltage, and a high specific capacitance of 141.4 F g−1 (5 mV s−1) from CV and 182 F g−1 (1 A g−1) from GCD at 100 °C is achieved, indicating an excellent electrochemical performance. The capacitor demonstrated 29.0 Wh kg−1 energy density and 13.3 kW kg−1 power density at 20 °C and 3 V potential, while 177 Wh kg−1 energy density and 82 kW kg−1 power density are achieved at higher temperature (100 °C). The FTIR analysis of the capacitor after electrochemical studies confirmed that no changes have occurred in the structure of the IL, indicating high electrochemical stability of the IL for supercapacitor applications in an extended temperature (−20 to 100 °C) and a wide potential range (3 V to 4.6 V).

  • 8.
    Khan, Inayat Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Catalysis and Nanomaterials Laboratory 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Sofian, Muhammad
    Catalysis and Nanomaterials Laboratory 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Badshah, Amin
    Catalysis and Nanomaterials Laboratory 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Khan, Muhammad Abdullah
    Department of Environmental Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
    Imran, Muhammad
    Department of Chemistry, Faculty of Sciences, King Khalid University, Abha, Saudi Arabia.
    Nadeem, Muhammad Arif
    Catalysis and Nanomaterials Laboratory 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Stable and Efficient PtRu Electrocatalysts Supported on Zn-BTC MOF Derived Microporous Carbon for Formic Acid Fuel Cells Application2020Ingår i: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, artikel-id 367Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Highly efficient, well-dispersed PtRu alloy nanoparticles supported on high surface area microporous carbon (MPC) electrocatalysts, are prepared and tested for formic acid oxidation reaction (FAOR). The MPC is obtained by controlled carbonization of a zincbenzenetricarboxylate metal-organic framework (Zn-BTC MOF) precursor at 950◦C, and PtRu (30 wt.%) nanoparticles (NPs) are prepared and deposited via a polyol chemical reduction method. The structural and morphological characterization of the synthesized electrocatalysts is carried out using powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), an energy dispersive X-ray (EDX) technique, and gas adsorption analysis (BET). The FAOR performance of the catalysts is investigated through cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). A correlation between high electrochemical surface area (ECSA) and high FAOR performance of the catalysts is observed. Among the materials employed, Pt1Ru2/MPC 950 with a high electrochemical surface area (25.3 m2 g −1 ) consequently showed superior activity of the FAOR (Ir = 9.50 mA cm−2 and Jm = 2,403 mA mg−1 Pt ) at room temperature, with improved tolerance and stability toward carbonaceous species. The superior electrochemical performance, and tolerance to CO-poisoning and long-term stability is attributed to the high surface area carbon support (1,455 m2 g −1 ) and high percentage loading of ruthenium (20 wt.%). The addition of Ru promotes the efficiency of electrocatalyst by offering FAOR via a bifunctional mechanism.

  • 9.
    Khan, Inayat Ali
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Wang, Yong-Lei
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Effect of structural variation in biomass-derived nonfluorinated ionic liquids electrolytes on the performance of supercapacitors2022Ingår i: Journal of Energy Chemistry, ISSN 2095-4956, E-ISSN 2096-885X, Vol. 69, s. 174-184Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is a growing interest in sustainable and high performance supercapacitors (SCs) operating at elevated temperatures as they are highly demanded in heat-durable electronics. Here, we present a biomass-derived nonfluorinated ionic liquid (IL) [P4444][HFuA] and its structural analogue [P4444][TpA] as electrolytes for supercapacitors comprising multiwall carbon nanotubes and activated charcoal (MWCNTs/AC) mixed carbon composite electrodes. A detailed investigation of the effect of scan rate, temperature, potential window and orientation of ions on the electrodes surfaces is performed. The supercapacitors exhibited relatively lower specific capacitance for both [P4444][HFuA] and [P4444][TpA] ILs at room temperature. However, the specific capacitance has significantly increased with an increase in temperature and potential window. The equivalent serie resistances of the SCs is deceased with increasing temperatures, which is a result of improved ionic conductivities of the IL electrolytes. In CV cycling at 60 °C, the capacitor with [P4444][HFuA] IL-based electrolyte retained about 90% of its initial capacitance, while the capacitor with [P4444][TpA] IL-based electrolyte retained about 83% of its initial capacitance. Atomistic computations revealed that the aromatic [FuA]− and [TpA]− anions displayed perpendicular distribution that can effectively neutralize charges on the carbon surfaces. However, the [HFuA]− anion exhibited somewhat tilted configurations on the carbon electrode surfaces, contributing to their outstanding capacitive performance in electrochemical devices.

  • 10.
    Khan, Inayat
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
    Badshah, Amin
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Assiri, Mohammed A.
    Department of Chemistry, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
    Nadeem, Muhammad Arif
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
    Zinc-Coordination Polymer-Derived Porous Carbon-Supported Stable PtM Electrocatalysts for Methanol Oxidation Reaction2021Ingår i: ACS Omega, E-ISSN 2470-1343, Vol. 6, nr 10, s. 6780-6790Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Porous carbon (PC) is obtained by carbonizing a zinc-coordination polymer (MOF-5) at 950 °C and PtM (M = Fe, Co, Ni, Cu, Zn) nanoparticles (NPs), which are deposited on PC using the polyol method. Structural and morphological characterizations of the synthesized materials are carried out by powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HRTEM), and the porosity was determined using a N2 adsorption/desorption technique. The results revealed that PtM NPs are alloyed in the fcc phase and are well dispersed on the surface of PC. The electrochemical results show that PtM/PC 950 catalysts have higher methanol oxidation reaction (MOR) performances than commercial Pt/C (20%) catalysts. After 3000 s of chronoamperometry (CA) test, the MOR performances decreased in the order of Pt1Cu1/PC 950 > Pt1Ni1/PC 950 > Pt1Fe1/PC 950 > Pt1Zn1/PC 950 > Pt1Co1/PC 950. The high MOR activities of the synthesized catalysts are attributed to the effect of M on methanol dissociative chemisorption and improved tolerance of Pt against CO poisoning. The high specific surface area and porosity of the carbon support have an additional effect in boosting the MOR activities. Screening of the first row transition metals (d5+n, n = 1, 2, 3, 4, 5) alloyed with Pt binary catalysts for MOR shows that Pt with d8 (Ni) and d9 (Cu) transition metals, in equivalent atomic ratios, are good anode catalysts for alcohol fuel cells.

     

  • 11.
    Khan, Syed Ishtiaq
    et al.
    Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan;Geoscience Advance Research Laboratories, Geological Survey of Pakistan, Islamabad, Pakistan.
    Ahmad, Sajjad
    Department of Health and Biological Sciences, Abasyn University, Peshawar 25000, Pakistan.
    Khan, Inayat Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Badshah, Amin
    Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
    Rauf, Muhammad Khawar
    Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
    Patujo, Jahangeer
    Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
    Siddiq, Muhammad Nasir
    Geoscience Advance Research Laboratories, Geological Survey of Pakistan, Islamabad, Pakistan.
    Kausar, Samia
    Department of Chemistry, University of Gujrat, Hafiz Hayat Campus, Gujrat 50700, Pakistan.
    Altaf, Ataf Ali
    Department of Chemistry, University of Okara, Okara-56300, Pakistan.
    Mononuclear copper(i) complexes of triphenylphosphine and N,N′-disubstituted thioureas as potential DNA binding chemotherapeutics2021Ingår i: New Journal of Chemistry, ISSN 1144-0546, E-ISSN 1369-9261, Vol. 45, nr 20, s. 8925-8935Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this work, nine new mixed-ligand complexes with the general formula [CuBr(TPP)2Tu1–9] were synthesized. The copper(I) complexes of triphenylphosphine (TPP) and different N,N′-disubstituted thioureas (Tu) were characterized via spectroscopic techniques including Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (1H, 13C, and 31P NMR), and single-crystal X-ray diffraction (SC-XRD). The complexes were synthesized via the direct reaction of bromo(tris(triphenylphosphine)copper(I)) [BrCu(PPh3)3] precursor and thiourea ligand solution under ambient conditions. Complexes 1, 2 and 3 crystallized in a triclinic system with the P  space group. Each complex is mononuclear, and the copper atom is tetrahedrally attached to two TPP groups through the phosphorous atom, one thiourea molecule through the sulfur atom and one bromine atom. The synthesized compounds were docked with a DNA macromolecule to predict their binding site and it was found that all molecules showed favorable binding to the DNA minor grooves. The DNA interaction studies of the representative complexes demonstrated their efficient DNA binding affinities. Based on the docking and DNA interaction results, complex 7 was found to be the best binder with a docking affinity of 382.2 kJ mol−1 and binding constant of 3.96 × 104 M−1. This compound tends to interact with the minor groove through the bromine atom positioning the side triphenylphosphine rings along the X-axis of the groove while keeping the 1-(2-chlorobenzyl)-3-(3-(trifluoromethyl)phenyl)thiourea ring on the outside.

  • 12.
    Khan, Zakir Zaman
    et al.
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Khan, Inayat Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Khan, Ishtiaq
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Wattoo, Muhammad Hamid Sarwar
    Ishfaq Ahmad Research Laboratories Complex, R-Block, Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan.
    Badshah, Amin
    Catalysis and Nanomaterials Lab 27, Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Pt and Co3O4 supported on ceria and zirconia for the catalytic reduction of N2O in the presence of CO2019Ingår i: Solid State Sciences, ISSN 1293-2558, E-ISSN 1873-3085, Vol. 98, artikel-id 106035Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ceria (CeO2) and zirconia (ZrO2) supported Pt and Co3O4-based nanocatalysts were synthesized and characterized by different instrumental techniques. The catalysts redox properties and active surface areas were evaluated using temperature-programmed reduction (TPR), temperature-programmed oxidation (TPO) and H2-pulse chemisorption, respectively. The catalysts were tested for the thermal oxidation of carbon monoxide (CO), reduction of nitrous oxide (N2O) and conversion of N2O/CO mixture (1:1 vol%) . In catalytic tests, Pt–Co3O4/CeO2 (10:10%) oxidized CO up to 100% at 25 °C and Co3O4/CeO2 (20%) reduced N2O up to 90% at 320 °C. Moreover, Pt–Co3O4/CeO2 (10:10%) converted N2O/CO mixture to N2/CO2 up to 90% at about 210 °C. The low-temperature catalytic activity of Pt–Co3O4/CeO2 (10:10%) for CO oxidation and N2O/CO mixture redox conversion were attributed to uniform particle size, metals and support proper combination and electron interaction.

  • 13.
    Shah, Faiz Ullah
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Gnezdilov, Oleg I.
    Institute of Physics, Kazan Federal University, 420008 Kazan, Russia.
    Khan, Inayat Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Filippov, Andrei
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik. Medical and Biological Physics, Kazan Medical University, 420012 Kazan, Russia.
    Slad, Natalia A.
    Institute of Polymers, Kazan National Research Technological University, 420015 Kazan, Russia.
    Johansson, Patrik
    Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden. ALISTORE-European Research Institute, CNRS FR 3104, Hub de l’Energie, 80039 Amiens, France.
    Structural and Ion Dynamics in Fluorine-Free Oligoether Carboxylate Ionic Liquid-Based Electrolytes2020Ingår i: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 124, nr 43, s. 9690-9700Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here, we investigate the physicochemical and electrochemical properties of fluorine-free ionic liquid (IL)-based electrolytes with two different cations, tetrabutylphosphonium, (P4,4,4,4)+, and tetrabutylammonium, (N4,4,4,4)+, coupled to a new anion, 2-[2-(2-methoxyethoxy)ethoxy]acetate anion (MEEA)−, for both neat and (P4,4,4,4)(MEEA) also doped with 10–40 mol % of Li(MEEA). We find relatively weaker cation–anion interactions in (P4,4,4,4)(MEEA) than in (N4,4,4,4)(MEEA), and for both ILs, the structural flexibility of the oligoether functionality in the anion results in low glass transition temperatures, also for the electrolytes made. The pulsed field gradient nuclear magnetic resonance (PFG NMR) data suggest faster diffusion of the (MEEA)− anion than (P4,4,4,4)+ cation in the neat IL, but the addition of a Li salt results in slightly lower mobility of the former than the latter and lower ionic conductivity. This agrees with the combined 7Li NMR and attenuated total reflection–Fourier transform infrared (ATR–FTIR) spectroscopy data, which unambiguously reveal preferential interactions between the lithium cations and the carboxylate groups of the IL anions, which also increased as a function of the lithium salt concentration. In total, these systems provide a stepping stone for further design of fluorine-free and low glass transition temperature IL-based electrolytes and also stress how crucial it is to control the strength of ion–ion interactions.

  • 14.
    Shah, Faiz Ullah
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Khan, Inayat Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Johansson, Patrik
    Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
    Comparing the Thermal and Electrochemical Stabilities of Two Structurally Similar Ionic Liquids2020Ingår i: Molecules, ISSN 1431-5157, E-ISSN 1420-3049, Vol. 25, nr 10, artikel-id 2388Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here we focus on the thermal and variable temperature electrochemical stabilities of two ionic liquids (ILs) having a common tributyloctyl phosphonium cation [P4,4,4,8]+ and two different orthoborate anions: bis(mandelato)borate [BMB] and bis(salicylato)borate [BScB]. The thermo-gravimetric analysis data suggest that [P4,4,4,8][BScB] is thermally more stable than [P4,4,4,8][BMB] in both nitrogen atmosphere and air, while the impedance spectroscopy reveals that [P4,4,4,8][BScB] has higher ionic conductivity than [P4,4,4,8][BMB] over the whole studied temperature range. In contrast, the electrochemical studies confirm that [P4,4,4,8][BMB] is more stable and exhibits a wider electrochemical stability window (ESW) on a glassy carbon electrode surface as compared to [P4,4,4,8][BScB]. A continuous decrease in the ESWs of both ILs is observed as a function of operation temperature.

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