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  • 1.
    Amin, Muhammad
    et al.
    Interdisciplinary Research Center for Hydrogen Technologies and Carbon Management (IRC-HTCM), King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia.
    Shah, Hamad Hussain
    Department of Engineering, University of Sannio, Benevento, Italy.
    Naveed, Abdul Basit
    Department of Chemistry, University of Louisville, Louisville, KY, United States.
    Iqbal, Amjad
    Faculty of Materials Engineering, Silesian University of Technology, Gliwice, Poland.
    Gamil, Yaser
    Department of Civil Engineering, School of Engineering, Monash University Malaysia, Subang Jaya, Selangor, Malaysia.
    Najeh, Taoufik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Life cycle assessment of iron-biomass supported catalyst for Fischer Tropsch synthesis2024In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 12, article id 1374739Article in journal (Refereed)
    Abstract [en]

    The iron-based biomass-supported catalyst has been used for Fischer-Tropsch synthesis (FTS). However, there is no study regarding the life cycle assessment (LCA) of biomass-supported iron catalysts published in the literature. This study discusses a biomass-supported iron catalyst’s LCA for the conversion of syngas into a liquid fuel product. The waste biomass is one of the source of activated carbon (AC), and it has been used as a support for the catalyst. The FTS reactions are carried out in the fixed-bed reactor at low or high temperatures. The use of promoters in the preparation of catalysts usually enhances C5+ production. In this study, the collection of precise data from on-site laboratory conditions is of utmost importance to ensure the credibility and validity of the study’s outcomes. The environmental impact assessment modeling was carried out using the OpenLCA 1.10.3 software. The LCA results reveals that the synthesis process of iron-based biomass supported catalyst yields a total impact score in terms of global warming potential (GWP) of 1.235E + 01 kg CO2 equivalent. Within this process, the AC stage contributes 52% to the overall GWP, while the preparation stage for the catalyst precursor contributes 48%. The comprehensive evaluation of the iron-based biomass supported catalyst’s impact score in terms of human toxicity reveals a total score of 1.98E−02 kg 1,4-dichlorobenzene (1,4-DB) equivalent.

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  • 2.
    Butylina, Svetlana
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Laboratory of Computational and Process Engineering, Lappeenranta-Lahti University of Technology, Lappeenranta, Finland.
    Geng, Shiyu
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Laatikainen, Katri
    Laboratory of Computational and Process Engineering, Lappeenranta-Lahti University of Technology, Lappeenranta, Finland.
    Oksman, Kristiina
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Mechanical & Industrial Engineering (MIE), University of Toronto, Toronto, ON, Canada.
    Cellulose Nanocomposite Hydrogels: From Formulation to Material Properties2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, article id 655Article in journal (Refereed)
    Abstract [en]

    Poly(vinyl alcohol) (PVA) hydrogels produced using the freeze-thaw method have attracted attention for a long time since their first preparation in 1975. Due to the importance of polymer intrinsic features and the advantages associated with them, they are very suitable for biomedical applications such as tissue engineering and drug delivery systems. On the other hand, there is an increasing interest in the use of biobased additives such as cellulose nanocrystals, CNC. This study focused on composite hydrogels which were produced by using different concentrations of PVA (5 and 10%) and CNC (1 and 10 wt.%), also, pure PVA hydrogels were used as references. The main goal was to determine the impact of both components on mechanical, thermal, and water absorption properties of composite hydrogels as well as on morphology and initial water content. It was found that PVA had a dominating effect on all hydrogels. The effect of the CNC addition was both concentration-dependent and case-dependent. As a general trend, addition of CNC decreased the water content of the prepared hydrogels, decreased the crystallinity of the PVA, and increased the hydrogels compression modulus and strength to some extent. The performance of composite hydrogels in a cyclic compression test was studied; the hydrogel with low PVA (5) and high CNC (10) content showed totally reversible behavior after 10 cycles.

  • 3.
    Dai, Zhengxing
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Chen, Yifeng
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Sun, Yunhao
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Zuo, Zhida
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Lu, Xiaohua
    State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Screening ionic liquids for developing advanced immobilization technology for CO2 separation2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 941352Article in journal (Refereed)
    Abstract [en]

    Developing immobilized-ionic liquids (ILs) sorbents is important for CO2 separation, and prior theoretically screening ILs is desirable considering the huge number of ILs. In this study, the compressibility of ILs was proposed as a new and additional index for screening ILs, and the developed predictive theoretical model, i.e., electrolyte perturbed-chain statistical associating fluid theory, was used to predict the properties for a wide variety of ILs in a wide temperature and pressure range to provide systematic data. In screening, firstly, the isothermal compressibilities of 272 ILs were predicted at pressures ranging from 1 to 6,000 bar and temperatures ranging from 298.15 to 323.15 K, and then 30 ILs were initially screened. Subsequently, the CO2 absorption capacities in these 30 ILs at temperatures from 298.15 to 323.15 K and pressures up to 50 bar were predicted, and 7 ILs were identified. In addition, the CO2 desorption enthalpies in these 7 ILs were estimated for further consideration. The performance of one of the screened ILs was verified with the data determined experimentally, evidencing that the screen is reasonable, and the consideration of IL-compressibility is essential when screening ILs for the immobilized-IL sorbents.

  • 4.
    Engelbrecht, Leon de Villiers
    et al.
    Department of Chemical and Geological Sciences, University of Cagliari, Cagliari, Italy.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Carbonaro, Carlo Maria
    Department of Physics, University of Cagliari, Cagliari, Italy.
    Laaksonen, Aatto
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Department of Chemical and Geological Sciences, University of Cagliari, Cagliari, Italy; Division of Physical Chemistry, Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden; Center of Advanced Research in Bionanoconjugates and Biopolymers, “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania; State Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Mocci, Francesca
    Department of Chemical and Geological Sciences, University of Cagliari, Cagliari, Italy.
    MD simulations explain the excess molar enthalpies in pseudo-binary mixtures of a choline chloride-based deep eutectic solvent with water or methanol2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 983281Article in journal (Refereed)
    Abstract [en]

    The addition of molecular liquid cosolvents to choline chloride (ChCl)-based deep eutectic solvents (DESs) is increasingly investigated for reducing the inherently high bulk viscosities of the latter, which represent a major obstacle for potential industrial applications. The molar enthalpy of mixing, often referred to as excess molar enthalpy HE—a property reflecting changes in intermolecular interactions upon mixing—of the well-known ChCl/ethylene glycol (1:2 molar ratio) DES mixed with either water or methanol was recently found to be of opposite sign at 308.15 K: Mixing of the DES with water is strongly exothermic, while methanol mixtures are endothermic over the entire mixture composition range. Knowledge of molecular-level liquid structural changes in the DES following cosolvent addition is expected to be important when selecting such “pseudo-binary” mixtures for specific applications, e.g., solvents. With the aim of understanding the reason for the different behavior of selected DES/water or methanol mixtures, we performed classical MD computer simulations to study the changes in intermolecular interactions thought to be responsible for the observed HE sign difference. Excess molar enthalpies computed from our simulations reproduce, for the first time, the experimental sign difference and composition dependence of the property. We performed a structural analysis of simulation configurations, revealing an intriguing difference in the interaction modes of the two cosolvents with the DES chloride anion: water molecules insert between neighboring chloride anions, forming ionic hydrogen-bonded bridges that draw the anions closer, whereas dilution of the DES with methanol results in increased interionic separation. Moreover, the simulated DES/water mixtures were found to contain extended hydrogen-bonded structures containing water-bridged chloride pair arrangements, the presence of which may have important implications for solvent applications.

  • 5.
    Filippov, Andrei
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Munavirov, Bulat
    System and Component Design, KTH Royal Institute of Technology, Stockholm, Sweden.
    Glavatskih, Sergei
    System and Component Design, KTH Royal Institute of Technology, Stockholm, Sweden. Department of Electromechanical, Systems and Metal Engineering, Ghent University, Ghent, Belgium. School of Chemistry, University of New South Wales, Sydney, Australia.
    Shah, Faiz Ullah
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Antzutkin, Oleg N.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. Department of Physics, Warwick University, Coventry, United Kingdom.
    Diffusion of Ions in Phosphonium Orthoborate Ionic Liquids Studied by 1H and 11B Pulsed Field Gradient NMR2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, article id 119Article in journal (Refereed)
    Abstract [en]

    Non-halogenated boron-based ionic liquids (ILs) composed of phosphonium cations and chelated orthoborate anions have high hydrolytic stability, low melting point and exceptional properties for various applications. This study is focused on ILs with the same type of cation, trihexyltetradecylphosphonium ([P6,6,6,14]+), and two orthoborate anions, such as bis(salicylato)borate ([BScB]−) and bis(oxalato)borate ([BOB]−). We compare the results of this study with our previous studies on ILs with bis(mandelato)borate ([BMB]−) and a variety of different cations (tetraalkylphosphonium, dialkylpyrrolidinium and dialkylimidazolium). The ion dynamics and phase behavior of these ILs is studied using 1H and 11B pulsed-field-gradient (PFG) NMR. PFG NMR is demonstrated to be a useful tool to elucidate the dynamics of ions in this class of phosphonium orthoborate ILs. In particular, the applicability of 11B PFG NMR for studying anions without 1H, such as [BOB]−, and the limitations of this technique to measure self-diffusion of ions in ILs are demonstrated and discussed in detail for the first time.

  • 6.
    Foorginezhad, Sahar
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Yu, Gangqiang
    Faculty of Environment and Life, Beijing University of Technology, Beijing, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Reviewing and screening ionic liquids and deep eutectic solvents for effective CO2 capture2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 951951Article, review/survey (Refereed)
    Abstract [en]

    CO2 capture is essential for both mitigating CO2 emissions and purifying/conditioning gases for fuel and chemical production. To further improve the process performance with low environmental impacts, different strategies have been proposed, where developing liquid green absorbent for capturing CO2 is one of the effective options. Ionic liquids (IL)/deep eutectic solvents (DES) have recently emerged as green absorbents with unique properties, especially DESs also benefit from facile synthesis, low toxicity, and high biodegradability. To promote their development, this work summarized the recent research progress on ILs/DESs developed for CO2 capture from the aspects of those physical- and chemical-based, and COSMO-RS was combined to predict the properties that are unavailable from published articles in order to evaluate their performance based on the key properties for different IL/DES-based technologies. Finally, top 10 ILs/DESs were listed based on the corresponding criteria. The shared information will provide insight into screening and further developing IL/DES-based technologies for CO2 capture.

  • 7.
    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 University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    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 Oxidation2021In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 9, article id 686969Article in journal (Refereed)
    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.

  • 8.
    Hua, Jing
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements.
    Shi, Yijun
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements.
    Non-corrosive Green Lubricant With Dissolved Lignin in Ionic Liquids Behave as Ideal Lubricants for Steel-DLC Applications2019In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 7, article id 857Article in journal (Refereed)
    Abstract [en]

    Diamond-like carbon (DLC)–steel contacts become more and more popular in the industry now. Since the surface chemical properties of DLC are quite different from those of iron, traditional formulated lubricants have problems to form tribo-chemical films, which are effective to improve the tribological performance for steel-steel contacts, on the surface of DLC. Thus, new lubricants formulation strategies are needed to be considered for steel-DLC applications. A kind of green lubricant (lignin-[Choline][L-Proline] (L-[CH][Pro])) without any traditional tribo-chemical active element, i.e., free of P, S, B, etc., was studied in this paper for the steel-DLC contact. To find the difference between this new ILs and the traditional lubricants, a commercially available fully formulated lubricant was used as a reference. An Optimol SRV-III oscillating friction and wear tester was used to evaluate the tribological performance. Three different kinds of commercially available DLC coatings (Tribobond 40(Cr + a-C:H:W), Tribobond 43 [(Cr+) a-C:H), and Tribobond 44(a-C:Cr)] were investigated. The results show that the ILs exhibit an obviously lower friction coefficient than that of the traditional commercially available fully formulated lubricant. Among those three DLC coatings, the (Cr+) a-C:H DLC coating exhibits the biggest improvement of wear resistance lubricated with the new ILs than that of the commercially available fully formulated lubricant. It's expected that its excellent tribological properties are attributed to the affinity of the ILs to the metal surface and the strength of the ionic liquids interactions by hydrogen bonding. Thus, forming strong physical adsorption strategy, instead of forming chemical tribo-films, is recommended to enhance the lubricating performance of lubricants for DLC.

  • 9.
    Karnaouri, Anthi C
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Topakas, Evangelos
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. School of Chemical Engineering, National Technical University of Athens.
    Matsakas, Leonidas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Rova, Ulrika
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Christakopoulos, Paul
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Fine-tuned enzymatic hydrolysis of organosolv pretreated forest materials for the efficient production of cellobiose2018In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 6, article id 128Article in journal (Refereed)
    Abstract [en]

    Non-digestible oligosaccharides (NDOs) are likely prebiotic candidates that have been related to the prevention of intestinal infections and other disorders for both humans and animals. Lignocellulosic biomass is the largest carbon source in the biosphere, therefore cello-oligosacharides (COS), especially cellobiose, are potentially the most widely available choice of NDOs. Production of COS and cellobiose with enzymes offers numerous benefits over acid-catalyzed processes, as it is milder, environmentally friendly and produces fewer by-products. Cellobiohydrolases (CBHs) and a class of endoglucanases (EGs), namely processive EGs, are key enzymes for the production of COS, as they have higher preference toward glycosidic bonds near the end of cellulose chains and are able to release soluble products. In this work, we describe the heterologous expression and characterization of two CBHs from the filamentous fungus Thermothelomyces thermophila, as well as their synergism with proccessive EGs for cellobiose release from organosolv pretreated spruce and birch. The properties, inhibition kinetics and substrate specific activities for each enzyme are described in detail. The results show that a combination of EGs belonging to Glycosyl hydrolase families 5, 6 and 9, with a CBHI and CBHII in appropriate proportions, can enhance the production of COS from forest materials, underpinning the potential of these biocatalysts in the production of NDOs.

  • 10.
    Khan, Inayat Ali
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. 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 Application2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, article id 367Article in journal (Refereed)
    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.

  • 11.
    Lellala, Kashinath
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Centre for Materials Science and Technology, University of Mysore, Mysore, India.
    Byrappa, K.
    Centre for Materials Science and Technology, University of Mysore, Mysore, India; Adichunchanagiri University, Mandya, India.
    Ceria Boosting on In Situ Nitrogen-Doped Graphene Oxide for Efficient Bifunctional ORR/OER Activity2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 889579Article in journal (Refereed)
    Abstract [en]

    In the present work, a highly efficient and excellent electrocatalyst material for bifunctional oxygen reduction/evolution reaction (ORR/OER) was synthesized using the microwave-assisted hydrothermal method. In brief, ultrafine hexagonal cerium oxide (CeO2) nanoparticles were tailored on the layered surface of in situ nitrogen-doped graphene oxide (NGO) sheets. The nanocomposites exhibited a high anodic onset potential of 0.925 V vs. RHE for ORR activity and 1.2 V for OER activity with a very high current density in 0.5 M KOH. The influence of oxygen cluster on Ce3+/Ce4+ ion decoration on outward/inward in situ nitrogen-coupled GO enhanced the physicochemical properties of composites and in turn increased electron transferability. The microwave-assisted hydrothermal coupling technique provides a higher density, active sites on CeO2@NGO composites, and oxygen deficiency structures in ultrafine Ce-O particles and boosts higher charge transferability in the composites. It is believed that the physical states of Ce-N- C, Ce-C=O, and a higher amount of oxygen participation with ceria increase the density of composites that in turn increases the efficiency. N-doped graphene oxide promotes high current conduction and rapid electron transferability while reducing the external transport resistance in oxygen electrocatalysis by sufficient mass transfer through in-built channels. This study may provide insights into the knowledge of Ce-enabled bifunctional activity to guide the design of a robust catalyst for electrochemical performance.

  • 12.
    Liu, Yanrong
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Yu, Hang
    State Key Laboratory of Material-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Sun, Yunhao
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Zeng, Shaojuan
    CAS Key Laboratory of Green Process and Engineering, Beijing Key Laboratory of Ionic Liquids Clean Process, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China.
    Zhang, Xiangping
    CAS Key Laboratory of Green Process and Engineering, Beijing Key Laboratory of Ionic Liquids Clean Process, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China. Zhengzhou Institute of Emerging Industrial Technology, Zhengzhou, China.
    Nie, Yi
    CAS Key Laboratory of Green Process and Engineering, Beijing Key Laboratory of Ionic Liquids Clean Process, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China. Zhengzhou Institute of Emerging Industrial Technology, Zhengzhou, China.
    Zhang, Suojiang
    CAS Key Laboratory of Green Process and Engineering, Beijing Key Laboratory of Ionic Liquids Clean Process, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China. School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Screening Deep Eutectic Solvents for CO2 Capture With COSMO-RS2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, no 82Article in journal (Refereed)
    Abstract [en]

    In this work, 502 experimental data for CO2 solubilities and 132 for Henry’s constantsof CO2 in DESs were comprehensively summarized from literatures and used for furtherverification and development of COSMO-RS. Large systematic deviations of 62.2, 59.6,63.0, and 59.1% for the logarithmic CO2 solubilities in the DESs (1:2, 1:3, 1:4, 1:5),respectively, were observed for the prediction with the original COSMO-RS, while thepredicted Henry’s constants of CO2 in the DESs (1:1.5, 1:2, 1:3, 1:4, 1:5) at temperaturesranging of 293.15–333.15 K are more accurate than the predicted CO2 solubility withthe original COSMO-RS. To improve the performance of COSMO-RS, 502 data pointsof CO2 solubility in the DESs (1:2, 1:3, 1:4, 1:5) were used for correcting COSMO-RSwith a temperature-pressure dependent parameter, and the CO2 solubility in the DES(1:6) was predicted to further verify the performance of the corrected model. The resultsindicate that the corrected COSMO-RS can significantly improve the model performancewith the ARDs decreasing down to 6.5, 4.8, 6.5, and 4.5% for the DESs (1:2, 1:3, 1:4, and 1:5), respectively, and the corrected COSMO-RS with the universal parameters can beused to predict the CO2 solubility in DESs with different mole ratios, for example, for theDES (1:6), the corrected COSMO-RS significantly improves the prediction with an ARD of10.3% that is much lower than 78.2% provided by the original COSMO-RS. Additionally,the result from COSMO-RS shows that the σ-profiles can reflect the strength of molecularinteractions between an HBA (or HBD) and CO2, determining the CO2 solubility, and thedominant interactions for CO2 capture in DESs are the H-bond and Van der Waals force,followed by the misfit based on the analysis of the predicted excess enthalpies.

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  • 13.
    Mushtaq, Irrum
    et al.
    Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Akhter, Zareen
    Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Shah, Faiz Ullah
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Tunable Self-Assembled Nanostructures of Electroactive PEGylated Tetra(Aniline) Based ABA Triblock Structures in Aqueous Medium2019In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 7, p. 1-10, article id 518Article in journal (Refereed)
    Abstract [en]

    PEGylated tetra(aniline) ABA triblock structure PEG-TANI-PEG (2) consisting of tetra(aniline) (TANI) and polyethylene glycol (PEG) was synthesized by coupling the tosylated-PEG to boc-protected NH2/NH2 TANI (1) through a simple nucleophilic substitution reaction. Deprotection of 2 resulted in a leucoemeraldine base state of TANI (2-LEB), which was oxidized to stable emeraldine base (2-EB) state. 2-EB was doped with 1 M HCl to emeraldine salt (2-ES) state. FTIR, 1H and 13C NMR and UV-Vis-NIR spectroscopy, and MS (ESI) was used for structural characterization. The synthesized triblock structure exhibited good electroactivity as confirmed by CV and UV-Vis-NIR spectroscopy. Self-assembling of the triblock structure in aqueous medium was assessed by DLS, TEM, and SEM. Spherical aggregates were observed with variable sizes depicting the effect of concentration and oxidation of 2-LEB. Further, the aggregates showed acid/base sensitivity as evaluated by doping and dedoping of 2-EB with 1 M HCl and 1 M NH4OH, respectively. Future applications in drug delivery and sensors are envisaged for such tunable self-assembled nanostructures in aqueous media.

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  • 14.
    Naz, Sadia
    et al.
    Institute of Chemistry, University of the Punjab, Lahore, Pakistan.
    Uroos, Maliha
    Institute of Chemistry, University of the Punjab, Lahore, Pakistan.
    Asim, Azmat Mehmood
    Institute of Chemistry, University of the Punjab, Lahore, Pakistan.
    Muhammad, Nawshad
    Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore, Pakistan.
    Shah, Faiz Ullah
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    One-Pot Deconstruction and Conversion of Lignocellulose Into Reducing Sugars by Pyridinium-Based Ionic Liquid–Metal Salt System2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, article id 236Article in journal (Refereed)
    Abstract [en]

    Constantly decreasing fossil resources and exceeding energy demands are the most alarming concerns now-a-days. The only way out is to develop efficient, safe and economic biomass processing protocols that can lead towards biofuels and fine chemicals. This research is one of such consequences involving the deconstruction and conversion of wheat straw carbohydrate constituents into reducing sugars via one-pot reaction promoted by Lewis acidic pyridinium based ionic liquids (PyILs) mixed with different metal salts (MCl). Various parameters such as the type of metal salt, loading amount of metal salt, time, temperature, particle size of biomass and water content which affect the deconstruction of wheat straw have been evaluated and optimized. Among the studied IL and metal salt systems, the best results were obtained with [BMPy]+CoCl3‒. The dinitrosalicylic acid (DNS) assay was used to determine the percentage of total reducing sugars (TRS) generated during treatment of wheat straw. The deconstructed wheat straw was characterized with various analytical tools i.e. FTIR, SEM and XRD analyses. The ionic liquid‒metal salt system was recycled for subsequent treatment of wheat straw. Statistical parameters were calculated from analysis of variance (ANOVA) at 0.05 level of confidence.

  • 15.
    Prajapati, Preeti
    et al.
    Department of Physics, University of Lucknow, Lucknow, India.
    Pandey, Jaya
    Department of Physics, University of Lucknow, Lucknow, India.
    Tandon, Poonam
    Department of Physics, University of Lucknow, Lucknow, India.
    Sinha, Kirti
    Department of Physics, University of Lucknow, Lucknow, India.
    Shimpi, Manishkumar R.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden.
    Molecular Structural, Hydrogen Bonding Interactions, and Chemical Reactivity Studies of Ezetimibe-L-Proline Cocrystal Using Spectroscopic and Quantum Chemical Approach2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 848014Article in journal (Refereed)
    Abstract [en]

    Ezetimibe (EZT) being an anticholesterol drug is frequently used for the reduction of elevated blood cholesterol levels. With the purpose of improving the physicochemical properties of EZT, in the present study, cocrystals of ezetimibe with L-proline have been studied. Theoretical geometry optimization of EZT-L-proline cocrystal, energies, and structure–activity relationship was carried out at the DFT level of theory using B3LYP functional complemented by 6-311++G(d,p) basis set. To better understand the role of hydrogen bonding, two different models (EZT + L-proline and EZT + 2L-proline) of EZT-L-proline cocrystal were studied. Spectral techniques (FTIR and FT-Raman) combined with quantum chemical methodologies were successfully implemented for the detailed vibrational assignment of fundamental modes. It is a zwitterionic cocrystal hydrogen bonded with the OH group of EZT and the COO− group of L-proline. The existence and strength of hydrogen bonds were examined by a natural bond orbital analysis (NBO) supported by the quantum theory of atoms in molecule (QTAIM). Chemical reactivity was reflected by the HOMO–LUMO analysis. A smaller energy gap in the cocrystal in comparison to API shows that a cocrystal is softer and chemically more reactive. MEPS and Fukui functions revealed the reactive sites of cocrystals. The calculated binding energy of the cocrystal from counterpoise method was −11.44 kcal/mol (EZT + L-proline) and −26.19 kcal/mol (EZT + 2L-proline). The comparative study between EZT-L-proline and EZT suggest that cocrystals can be better used as an alternative to comprehend the effect of hydrogen bonding in biomolecules and enhance the pharmacological properties of active pharmaceutical ingredients (APIs).

  • 16.
    Rohlmann, Patrick
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Munavirov, Bulat
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Furó, István
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Rutland, Mark William
    KTH Royal Institute of Technology, Stockholm, Sweden. Surfaces, Processes and Formulation, RISE Research Institutes of Sweden, Stockholm, Sweden.
    Glavatskih, Sergei
    KTH Royal Institute of Technology, Stockholm, Sweden. Department of Electrical Energy, Metals, Mechanical Constructions and Systems, Ghent University, Ghent, Belgium.
    Non-halogenated Ionic Liquid Dramatically Enhances Tribological Performance of Biodegradable Oils2019In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 7, article id 98Article in journal (Refereed)
    Abstract [en]

    It is demonstrated that a phosphonium orthoborate ionic liquid may serve as a wear reducing additive in biodegradable oils at steel-steel surfaces in the boundary lubrication regime. Tribological tests were performed in a ball-on-three plate configuration. A set of surface characterization techniques—SEM/EDS, FIB and white light interferometry were used to characterize surfaces following the tribotests and to observe the formation of any tribofilms. 11B NMR was used to follow changes in the composition of the ionic-liquid-oil blends and to identify boron-containing decomposition products after the tribotests. The ionic liquid reduces the wear of steel surfaces by up to 92% compared to the neat oil at 90°C; it is shown that the reduction in wear can be correlated with the formation of boron enriched patches in the boundary films.

  • 17.
    Sarmad, Shokat
    et al.
    Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University, Umeå, Sweden.
    Taghi Zafarani-Moattar, Mohammed
    Physical Chemistry Department, University of Tabriz, Tabriz, Iran.
    Nikjoo, Dariush
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Mikkola, Jyri-Pekka
    Industrial Chemistry & Reaction Engineering, John Gadolin Process Chemistry Centre, Åbo Akademi University, Turku, Finland.
    How Different Electrolytes Can Influence the Aqueous Solution Behavior of 1-Ethyl-3-Methylimidazolium Chloride: A Volumetric, Viscometric, and Infrared Spectroscopy Approach2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, article id 593786Article in journal (Refereed)
    Abstract [en]

    The density, sound velocity, and viscosity of 1-ethyl-3-methylimidazolium chloride [C2mim]Cl in pure water and aqueous solutions of some electrolytes such as potassium chloride, potassium carbonate, and potassium phosphate (weight fraction of salt fixed at ws = 0. 11) have been measured over a wide range of temperatures from 298.15 to 318.15 K. The obtained experimental data have been used to compute various volumetric, compressibility, and viscometric parameters, e.g., apparent molar properties, limiting apparent molar and transfer properties. The co-sphere overlap model was employed to describe the dominant intermolecular interactions in the ternary solutions. Additionally, the structure making/breaking nature of the [C2mim]Cl in the ternary solutions has been discussed in terms of Hepler's constant and the temperature derivative of viscosity B-coefficient (dB/dT). The activation free energy of solvent and solute, activation enthalpy, and activation entropy have been calculated by the application of transition state theory. The calculated parameters have been interpreted in the sense of solvent–solute and solute–solute interactions. The Fourier transform infrared (FTIR) studies also have been done for the studied systems. Volumetric, acoustic, viscometric, and spectroscopic studies can render some evidence and help to understand the aqueous solution behavior of ionic liquids.

  • 18.
    Shah, Faiz Ullah
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    An, Rong
    Department of Materials Science and Engineering, Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, Nanjing, China.
    Muhammad, Nawshad
    Interdisciplinary Research Centre in Biomedical Materials (IRCBM) COMSATS University Islamabad, Islamabad, Pakistan.
    Editorial: Properties and Applications of Ionic Liquids in Energy and Environmental Science2020In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 8, article id 627213Article in journal (Refereed)
  • 19.
    Sun, Yunhao
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Jiangsu Key Laboratory of Process Enhancement and New Energy Equipment Technology, School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, China.
    Dai, Zhengxing
    State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Shen, Gulou
    National and Local Joint Engineering Research Center for Deep Utilization Technology of Rock-Salt Resource, Faculty of Chemical Engineering, Huaiyin Institute of Technology, Huaian, China.
    Lu, Xiaohua
    State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Ling, Xiang
    Jiangsu Key Laboratory of Process Enhancement and New Energy Equipment Technology, School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Accelerate the Electrolyte Perturbed-Chain Statistical Associating Fluid Theory-Density Functional Theory Calculation With the Chebyshev Pseudo-Spectral Collocation Method. Part II. Spherical Geometry and Anderson Mixing2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 9, article id 801551Article in journal (Refereed)
    Abstract [en]

    To improve the efficiency of electrolyte perturbed-chain statistical associatingfluidtheory–density functional theory (ePC-SAFT-DFT) calculation of the confined system, inthis work,first, the Chebyshev pseudo-spectral collocation method was extended to thespherical pores. Second, it was combined with the Anderson mixing algorithm toaccelerate the iterative process. The results show that the Anderson mixing algorithmcan reduce the computation time significantly. Finally, based on the accelerated ePC-SAFT-DFT program, a systematic study of the effects of the temperature, pressure, poresize, and pore shape on the CO2solubilities in the ionic liquids (ILs) confined inside the silicananopores was conducted. Based on the simulation results, to obtain high CO2solubilitiesin the ILs confined in silica, a better option is to use the silica material with a narrowspherical pore, and the IL-anion should be selected specifically considering that it has amore significant impact on the absorption enhancement effect.

  • 20.
    Vasiliu, Tudor
    et al.
    Centre of Advanced Research in Bionanoconjugates and Biopolymers “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania.
    Mocci, Francesca
    Dipartimento di Scienze Chimiche e Geologiche, Cagliari University, Cagliari, Italy.
    Laaksonen, Aatto
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Centre of Advanced Research in Bionanoconjugates and Biopolymers “Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania; Dipartimento di Scienze Chimiche e Geologiche, Cagliari University, Cagliari, Italy; Division of Physical Chemistry, Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden; State Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Engelbrecht, Leon De Villiers
    Dipartimento di Scienze Chimiche e Geologiche, Cagliari University, Cagliari, Italy.
    Perepelytsya, Sergiy
    Bogolyubov Institute for Theoretical Physics of the NAS of Ukraine, Kyiv, Ukraine.
    Caging Polycations: Effect of Increasing Confinement on the Modes of Interaction of Spermidine3+ With DNA Double Helices2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 836994Article in journal (Refereed)
    Abstract [en]

    Polyamines have important roles in the modulation of the cellular function and are ubiquitous in cells. The polyamines putrescine2+, spermidine3+, and spermine4+ represent the most abundant organic counterions of the negatively charged DNA in the cellular nucleus. These polyamines are known to stabilize the DNA structure and, depending on their concentration and additional salt composition, to induce DNA aggregation, which is often referred to as condensation. However, the modes of interactions of these elongated polycations with DNA and how they promote condensation are still not clear. In the present work, atomistic molecular dynamics (MD) computer simulations of two DNA fragments surrounded by spermidine3+ (Spd3+) cations were performed to study the structuring of Spd3+ “caged” between DNA molecules. Microsecond time scale simulations, in which the parallel DNA fragments were constrained at three different separations, but allowed to rotate axially and move naturally, provided information on the conformations and relative orientations of surrounding Spm3+ cations as a function of DNA-DNA separation. Novel geometric criteria allowed for the classification of DNA-Spd3+ interaction modes, with special attention given to Spd3+ conformational changes in the space between the two DNA molecules (caged Spd3+). This work shows how changes in the accessible space, or confinement, around DNA affect DNA-Spd3+ interactions, information fundamental to understanding the interactions between DNA and its counterions in environments where DNA is compacted, e.g. in the cellular nucleus.

  • 21.
    Verma, Priya
    et al.
    Department of Physics, University of Lucknow, Lucknow, India.
    Srivastava, Anubha
    Department of Physics, University of Lucknow, Lucknow, India.
    Srivastava, Karnica
    Department of Physics, Isabella Thoburn (I.T.) College, Lucknow, India.
    Tandon, Poonam
    Department of Physics, University of Lucknow, Lucknow, India.
    Shimpi, Manishkumar R.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden.
    Molecular Structure, Spectral Investigations, Hydrogen Bonding Interactions and Reactivity-Property Relationship of Caffeine-Citric Acid Cocrystal by Experimental and DFT Approach2021In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 9, article id 708538Article in journal (Refereed)
    Abstract [en]

    The pharmaceutical cocrystal of caffeine-citric acid (CAF-CA, Form II) has been studied to explore the presence of hydrogen bonding interactions and structure-reactivity-property relationship between the two constituents CAF and Citric acid. The cocrystal was prepared by slurry crystallization. Powder X-ray diffraction (PXRD) analysis was done to characterize CAF-CA cocrystal. Also, differential scanning calorimetry (DSC) confirmed the existence of CAF-CA cocrystal. The vibrational spectroscopic (FT-IR and FT-Raman) signatures and quantum chemical approach have been used as a strategy to get insights into structural and spectral features of CAF-CA cocrystal. There was a good correlation among the experimental and theoretical results of dimer of cocrystal, as this model is capable of covering all nearest possible interactions present in the crystal structure of cocrystal. The spectroscopic results confirmed that (O33-H34) mode forms an intramolecular (C25 = O28∙∙∙H34-O33), while (O26-H27) (O39-H40) and (O43-H44) groups form intermolecular hydrogen bonding (O26-H27∙∙∙N24-C22, O39-H40∙∙∙O52 = C51 and O43-H44∙∙∙O86 = C83) in cocrystal due to red shifting and increment in bond length. The quantum theory of atoms in molecules (QTAIM) analysis revealed (O88-H89∙∙∙O41) as strongest intermolecular hydrogen bonding interaction with interaction energy −12.4247 kcal mol−1 in CAF-CA cocrystal. The natural bond orbital analysis of the second-order theory of the Fock matrix highlighted the presence of strong interactions (N∙∙∙H and O∙∙∙H) in cocrystal. The HOMO-LUMO energy gap value shows that the CAF-CA cocrystal is more reactive, less stable and softer than CAF active pharmaceutical ingredients. The electrophilic and nucleophilic reactivities of atomic sites involved in intermolecular hydrogen bond interactions in cocrystal have been demonstrated by mapping electron density isosurfaces over electrostatic potential i.e. plotting molecular electrostatic potential (MESP) map. The molar refractivity value of cocrystal lies within the set range by Lipinski and hence it may be used as orally active form. The results show that the physicochemical properties of CAF-CA cocrystal are enhanced in comparison to CAF (API).

     

  • 22.
    Verma, Priya
    et al.
    Department of Physics, University of Lucknow, Lucknow, India.
    Srivastava, Anubha
    Department of Physics, University of Lucknow, Lucknow, India.
    Tandon, Poonam
    Department of Physics, University of Lucknow, Lucknow, India.
    Shimpi, Manishkumar R.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden.
    Experimental and Quantum Chemical Studies of Nicotinamide-Oxalic Acid Salt: Hydrogen Bonding, AIM and NBO Analysis2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 855132Article in journal (Refereed)
    Abstract [en]

    The computational modeling supported with experimental results can explain the overall structural packing by predicting the hydrogen bond interactions present in any cocrystals (active pharmaceutical ingredients + coformer) as well as salts. In this context, the hydrogen bonding synthons, physiochemical properties (chemical reactivity and stability), and drug-likeliness behavior of proposed nicotinamide–oxalic acid (NIC–OXA) salt have been reported by using vibrational spectroscopic signatures (IR and Raman spectra) and quantum chemical calculations. The NIC–OXA salt was prepared by reactive crystallization method. X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC) techniques were used for the characterization and validation of NIC–OXA salt. The spectroscopic signatures revealed that (N7–H8)/(N23–H24) of the pyridine ring of NIC, (C═O), and (C–O) groups of OXA were forming the intermolecular hydrogen bonding (N–H⋯O–C), (C–H⋯O═C), and (N–H⋯O═C), respectively, in NIC–OXA salt. Additionally, the quantum theory of atoms in molecules (QTAIM) showed that (C10–H22⋯O1) and (C26–H38⋯O4) are two unconventional hydrogen bonds present in NIC–OXA salt. Also, the natural bond orbital analysis was performed to find the charge transfer interactions and revealed the strongest hydrogen bonds (N7–H8⋯O5)/(N23–H24⋯O2) in NIC–OXA salt. The frontier molecular orbital (FMO) analysis suggested more reactivity and less stability of NIC–OXA salt in comparison to NIC–CA cocrystal and NIC. The global and local reactivity descriptors calculated and predicted that NIC–OXA salt is softer than NIC–CA cocrystal and NIC. From MESP of NIC–OXA salt, it is clear that electrophilic (N7–H8)/(N23–H24), (C6═O4)/(C3═O1) and nucleophilic (C10–H22)/(C26–H38), (C6–O5)/(C3–O2) reactive groups in NIC and OXA, respectively, neutralize after the formation of NIC–OXA salt, confirming the presence of hydrogen bonding interactions (N7–H8⋯O5–C6) and (N23–H24⋯O2–C3). Lipinski’s rule was applied to check the activeness of salt as an orally active form. The results shed light on several features of NIC–OXA salt that can further lead to the improvement in the physicochemical properties of NIC.

  • 23.
    Zhang, Zhibo
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Wang, Hui
    State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Nie, Yi
    Zhengzhou Institute of Emerging Industrial Technology, Zhengzhou, China; Beijing Key Laboratory of Ionic Liquids Clean Process, CAS Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China.
    Zhang, Xiangping
    Beijing Key Laboratory of Ionic Liquids Clean Process, CAS Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Natural Deep Eutectic Solvents Enhanced Electro-Enzymatic Conversion of CO2 to Methanol2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 894106Article in journal (Refereed)
    Abstract [en]

    Electro-enzymatic conversion of CO2 offers a promising solution for CO2 utilization, while the conversion rate and efficiency were disappointing. To address the challenge, four kinds of natural deep eutectic solvents (NADES) with desirable biocompatibility were developed for the first time and used as the co-electrolyte in the electro-enzymatic conversion of CO2. As a result, the SerGly-based solution presents high CO2 solubility and high electrocatalytic activity, compared to the conventional buffer. By applying SerGly in the electro-enzymatic conversion of CO2, the yield of the product (methanol) is two times higher than that in the Tris-HCl buffer (0.22 mM) and 16 times higher than the control reaction.

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