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2021

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Articles 31 - 60 of 204

Full-Text Articles in Physical Chemistry

Electrochemical Synthesis Of P-(Β-Hydroxyethyl Sulfone) Aniline, Hao Guo, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang Oct 2021

Electrochemical Synthesis Of P-(Β-Hydroxyethyl Sulfone) Aniline, Hao Guo, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

Para-ester is the most important intermediate for the preparation of ethylene sulfone type reactive dyes, which is usually used in the dyeing of cellulose fibers and synthetic fibers. P-(β-hydroxyethyl sulfone) aniline is an important intermediate for the synthesis of para-ester. In this paper, p-(β-hydroxyethyl sulfone) aniline was prepared by electrochemical method, having the advantages of simple process, mild reaction condition, less environmental pollution, easy reaction control and so on. It has strong development potential and industrial application prospect. The electrochemical reduction of p-nitrophenyl-β-hydroxyethyl sulfone on a lead plate electrode to prepare p-(β-hydroxyethyl …

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Numerical Study On The Influences Of Flow Channel And Rib Width Ratio On The Performance Of Gas Diffusion Layer, Rong-Qiang Wei, Shi-An Li, Yi-Hui Liu, Zhi Yang, Qiu-Wan Shen, Guo-Gang Yang Oct 2021

Numerical Study On The Influences Of Flow Channel And Rib Width Ratio On The Performance Of Gas Diffusion Layer, Rong-Qiang Wei, Shi-An Li, Yi-Hui Liu, Zhi Yang, Qiu-Wan Shen, Guo-Gang Yang

Journal of Electrochemistry

Proton exchange membrane fuel cell (PEMFC) has the advantages of low noise, high power density, and zero emission. It is widely used in ships, automobiles, aviation and other fields. PEMFC is composed of bipolar plate (BP), gas diffusion layer (GDL), catalytic layer (CL) and proton exchange membrane (PEM). GDL has a supporting catalytic layer and proton exchange membrane, which provides gas diffusion for the reaction and a channel for the reaction to produce water, and transmits the anodic oxidation reaction. In the assembly of fuel cells, a certain assembly pressure is required to ensure air-tightness and effective conductivity. The assembly …

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Mathematical Expression And Quantitative Analysis Of Impedance Spectrum On The Interface Of Glassy Carbon Electrode, Lei Cheng, Pu-Xuan Yan, You-Jun Fan, Hua-Hong Zou, Hong Liang Oct 2021

Mathematical Expression And Quantitative Analysis Of Impedance Spectrum On The Interface Of Glassy Carbon Electrode, Lei Cheng, Pu-Xuan Yan, You-Jun Fan, Hua-Hong Zou, Hong Liang

Journal of Electrochemistry

Glassy carbon electrode (GCE) is a common basic electrode for various electrochemical sensors, and the detection properties are determined by its interfacial characteristics. In this paper, we established an equivalent circuit including electrolyte resistance (Rel), charge transport resistance (Rct), diffusion impedance (Rdi, Cdi), electrochemical (oxidation/reduction) reaction impedance (RR, CR), surface adsorption impedance (Rads , Cads), double-layer capacitance (CDL), and derived the mathematical expression for the equivalent circuit. The Rel and CDL are contributed by inactive …

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Preparation Of Modified Titanium Based Pbo2 Electrode And Its Rapid Detection Of Cod, Qi Sun, Yan-He Han, Xiao-Lu Fu Oct 2021

Preparation Of Modified Titanium Based Pbo2 Electrode And Its Rapid Detection Of Cod, Qi Sun, Yan-He Han, Xiao-Lu Fu

Journal of Electrochemistry

In the traditional Ti/β-PbO2 electrode, the crystal lattice difference between β-PbO2 and Ti matrix is large, and the prepared electrode is easy to fall off and has a short service life. It needs to be modified in actual use. Based on the advantages of α-PbO2 material and Ag material in terms of adhesion and conductivity, respectively, the above two materials are selected as the intermediate layer of Ti/β-PbO2 electrode to improve electrode performance. In this paper, by preparing Ti/α/β-PbO2 and Ti/Ag/β-PbO2 electrodes …

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Fundamentals Of Electrochemical Impedance Spectroscopy For Macrohomogeneous Porous Electrodes, Xiang Li, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jia Wang, Yang Liu, Yu-Feng Zhao, Juan Wang, Jiu-Jun Zhang Oct 2021

Fundamentals Of Electrochemical Impedance Spectroscopy For Macrohomogeneous Porous Electrodes, Xiang Li, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jia Wang, Yang Liu, Yu-Feng Zhao, Juan Wang, Jiu-Jun Zhang

Journal of Electrochemistry

Electrochemical impedance spectroscopy (EIS) can be used to diagnose charge transfer reactions and mass transport in porous electrodes. The charge transfer reactions include interfacial charge accumulation and charge conduction as well as electrochemical reaction. In this paper, the complex phasor method is developed under the macrohomogeneous assumption to build an impedance model of porous electrodes for clarifying several vague expressions in the traditional approaches. The following researches are carried out: (1) Identifying characteristic parameters for the porous electrodes, including electrode electronic conductivity σ1, electrolyte ionic conductivity σ2, interface charge transfer conductivity gct, unit area …

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Janus-Tinbco2 For Hydrogen Evolution Reaction With High Conductivity And Catalytic Activity, Li-Li Xu, Dong-Yan Ren, Xiao-Feng Zhao, Yong Yi Oct 2021

Janus-Tinbco2 For Hydrogen Evolution Reaction With High Conductivity And Catalytic Activity, Li-Li Xu, Dong-Yan Ren, Xiao-Feng Zhao, Yong Yi

Journal of Electrochemistry

Exploring the potential hydrogen evolution reaction (HER) catalysts with the high activity and high conductivity has always been a hot spot in the research of renewable energy development. Ti2C, as one of the 2D-MXene, has excellent properties relating to many active sites, mechanical stability, conductivity, etc., and has become a potential HER catalyst. However, the modification of the surface of Ti2C by terminal O will reduce the conductivity, thereby limiting the transport of electrons between the valence band and the conduction band. In this study, an electric double layer Janus-TiNbCO2 was constructed by Nb doping. …

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Application Of Ti/Ruo2-Iro2-Sno2-Sb2O5 Anode In Rural Drinking Water Disinfection, Jing-Ru Guo, Xue-Jiao Zhang, Shuai Liao, Xue-Ming Chen Oct 2021

Application Of Ti/Ruo2-Iro2-Sno2-Sb2O5 Anode In Rural Drinking Water Disinfection, Jing-Ru Guo, Xue-Jiao Zhang, Shuai Liao, Xue-Ming Chen

Journal of Electrochemistry

Sodium hypochlorite disinfection has many advantages, including reliable operation, low cost, easily available raw materials. It is, therefore, suitable for disinfection of drinking water in remote rural areas. The service life and chlorine evolution efficiency of the anode are the main factors restricting the performance of the sodium hypochlorite generator. The special conditions of frequent shutdown and low electrolyte concentration in the rural drinking water application also put forward high requirements on the performance of the anode. In this study, Ti/RuO2-IrO2-SnO2-Sb2O5,a new-type and efficient chlorine evolution anode, was prepared by …

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Study On Improving The Production Of Ammonium Persulfate By Ion Membrane Electrolysis, Yi-Hang Qu, Min Cui, Cong Zhang, Chong Li, Peng Li, Ju-Jie Ren Oct 2021

Study On Improving The Production Of Ammonium Persulfate By Ion Membrane Electrolysis, Yi-Hang Qu, Min Cui, Cong Zhang, Chong Li, Peng Li, Ju-Jie Ren

Journal of Electrochemistry

In china, the production of ammonium persulfate in factories mostly adopts the electrolysis method with simple process and high purity. However, there exists the problem of high energy consumption in the electrolysis process, which restricts the further development of ammonium persulfate in many fields. Aiming at this phenomenon, the equipment and technology to produce ammonium persulfate using electrolysis were designed and studied in order to reduce energy consumption. A new type of zero-pole distance and ion-exchange membrane industrial electrolytic cell was provided for the electrolysis production of ammonium persulfate. An ion-exchange membrane was used to separate the electrolytic cell into …

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Effect Of Alkyl Chain Length Of Symmetrical Quaternary Ammonium Hydroxide On Oxalic Acid Electroreduction Reaction, Bo Huang, Xin-Sheng Zhang, Dong-Fang Niu, Shuo-Zhen Hu Oct 2021

Effect Of Alkyl Chain Length Of Symmetrical Quaternary Ammonium Hydroxide On Oxalic Acid Electroreduction Reaction, Bo Huang, Xin-Sheng Zhang, Dong-Fang Niu, Shuo-Zhen Hu

Journal of Electrochemistry

Glyoxylic acid with the dual characteristics of acid and aldehyde is an important chemical raw material and organic synthesis intermediate, which is extensively used in the perfumery, pharmaceutical and fine chemical industries. A family of symmetric quaternary ammonium hydroxides (QAHs) with different alkyl chain lengths was used as the additives in generating glyoxylic acid from oxalic acid electroreduction reaction (OAER). The effects of alkyl chain length on OAER and the corresponding side reaction, i.e., hydrogen evolution reaction (HER), were investigated. Linear sweep voltammetric (LSV) results showed that the adsorption of the additives suppressed more on the HER than that on …

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Synthesis Of Nickel Phosphide/Nitrogen Phosphorus Co-Doped Carbon And Its Application In Lithium Ion Batteries, Jian Hu, Yan-Shuang Meng, Qian-Ru Hu Oct 2021

Synthesis Of Nickel Phosphide/Nitrogen Phosphorus Co-Doped Carbon And Its Application In Lithium Ion Batteries, Jian Hu, Yan-Shuang Meng, Qian-Ru Hu

Journal of Electrochemistry

In recent years, the nickel-based phosphide has drawn great attention because of its low intercalation/deintercalation platform and lower polarization compared to sulfides and oxides as anodes for next-generation high-energy lithium-ion batteries. The Ni2P anode can deliver high theoretical specific capacity of 542 mAh·g-1, but it subject to a conversion reaction mechanism, which make them unsuitable for commercial applications. The agglomeration of Ni2P nanoparticles during material fabrication and the structural deterioration of electrode associated with large volume change during charge-discharge process lead to poor cycle stability and low utilization of active materials. Meanwhile, the low …

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National Chemistry Week: From Irl To The Web, Ilayda Kelley, Daniela Mesa Sanchez Oct 2021

National Chemistry Week: From Irl To The Web, Ilayda Kelley, Daniela Mesa Sanchez

Purdue Journal of Service-Learning and International Engagement

National Chemistry Week, an outreach program initiated by the American Chemical Society (ACS), encourages scientists to bring their love of chemistry to their community. Celebrated nationwide, ACS invites businesses, schools, and individuals to organize and participate in community events to promote the value of chemistry in everyday life. The Purdue graduate student chapter of Iota Sigma Pi, a national honor society for women in chemistry, annually organizes one such celebration. On a normal year, this event is a large logistical undertaking in which 100+ volunteers go directly to over 70 local elementary school classrooms and perform a series of activities …

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Synergistic Anticancer Response Of Curcumin And Piperine Loaded Lignin-G-P (Nipam-Co-Dmaema) Gold Nanogels Against Glioblastoma Multiforme, Xinyi Zhao, Bilal Javad, Daxing Cui, James Curtin, Furong Tian Oct 2021

Synergistic Anticancer Response Of Curcumin And Piperine Loaded Lignin-G-P (Nipam-Co-Dmaema) Gold Nanogels Against Glioblastoma Multiforme, Xinyi Zhao, Bilal Javad, Daxing Cui, James Curtin, Furong Tian

Articles

Glioblastoma multiforme (GBM) is the most aggressive and commonly diag- 11 nosed brain cancer and presents a strong resistance to routine chemotherapeutic drugs. 12 The present study involves the synthesis of Lignin-g- p (NIPAM-co-DMAEMA) gold 13 nanogel, loaded with curcumin and piperine to treat GBM. The application has three 14 functions: (1) overcome the limitations of biodistribution, (2) enhance the toxicity of an- 15 ticancer drugs against GBM, (3) identify the uptake pathway. Atom transfer radical 16 polymerization was used to synthesize the Lignin-g-PNIPAM network, crosslinked with 17 the gold nanoparticles (GNPs) to self-assemble into nanogels. The size distribution and …

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Physical Chemistry, Ruth E. Stark Oct 2021

Physical Chemistry, Ruth E. Stark

Open Educational Resources

This is a provisional syllabus for Physical Chemistry I (Thermodynamics), to be taught using an OER Textmap in Fall, 2021.

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Controlling Degradation With Force And Light, Brad Davis Sep 2021

Controlling Degradation With Force And Light, Brad Davis

Dissertations

Stimuli-responsive polymers respond to changes in their environment by altering their physical and chemical properties. Their responsiveness allows them to be used as sensors, mechanical actuators, delivery systems, and can yield either elongated lifetimes through healing mechanisms or shortened lifetimes through triggered degradation. Still a growing field in polymer science, researchers seek to expand the capabilities of these materials by improving their specificity, range, and mechanisms of both the stimuli and the response. The work presented explores stimuli-responsive materials, focusing on mechanical and light stimuli, and how to gain control of the response by specific changes in the polymeric material. …

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Two-Dimensional Monolayer Salt Nanostructures Can Spontaneously Aggregate Rather Than Dissolve In Dilute Aqueous Solutions, Wenhui Zhao, Yunxiang Sun, Weiduo Zhu, Jian Jiang, Xiaorong Zhao, Dongdong Lin, Wenwu Xu, Xiangmei Duan, Joseph S. Francisco, Xiao Cheng Zeng Sep 2021

Two-Dimensional Monolayer Salt Nanostructures Can Spontaneously Aggregate Rather Than Dissolve In Dilute Aqueous Solutions, Wenhui Zhao, Yunxiang Sun, Weiduo Zhu, Jian Jiang, Xiaorong Zhao, Dongdong Lin, Wenwu Xu, Xiangmei Duan, Joseph S. Francisco, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

It is well known that NaCl salt crystals can easily dissolve in dilute aqueous solutions at room temperature. Herein, we reported the first computational evidence of a novel salt nucleation behavior at room temperature, i.e., the spontaneous formation of two-dimensional (2D) alkali chloride crystalline/non-crystalline nanostructures in dilute aqueous solution under nanoscale confinement. Microsecond-scale classical molecular dynamics (MD) simulations showed that NaCl or LiCl, initially fully dissolved in confined water, can spontaneously nucleate into 2D monolayer nanostructures with either ordered or disordered morphologies. Notably, the NaCl nanostructures exhibited a 2D crystalline square-unit pattern, whereas the LiCl nanostructures adopted non-crystalline 2D hexagonal …

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A Compendium Of Inorganic Photochemistry: Synthetic And Spectroscopic Discoveries, Sebastian B. Vittardi Sep 2021

A Compendium Of Inorganic Photochemistry: Synthetic And Spectroscopic Discoveries, Sebastian B. Vittardi

Chemistry and Chemical Biology ETDs

This dissertation reports and examines contributions made in the advancement of inorganic photochemistry. Empirically driven assessments are allotted to the interplay between ligand sets, excited states, and photochemistry observed in metal complexes. A methodical spectroscopic examination is provided for oligothiophene-sensitized lanthanides. Their excited state dynamics were elucidated by femtosecond pump-probe spectroscopy and used to develop a model explaining their wavelength-dependent dual functionality. Iron (II) cyanide and isocyanides are evaluated to identify the efficacy of strong-field ligands in promoting charge-transfer excited states. Fundamentals of ligand field theory helped conceptualize the synthetically tunable parameters and effects transposed to their absorption dynamics. Transition …

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Spectral Analysis Of A New Electronic Transition Of Platinum Fluoride, Ptf, Carol Welch Sep 2021

Spectral Analysis Of A New Electronic Transition Of Platinum Fluoride, Ptf, Carol Welch

Undergraduate Research Symposium

The electronic landscape of platinum containing molecules has been the focus of numerous spectroscopic studies in recent years, because of the difficulty in describing electronic structure theoretically due to electronic correlations and relativistic effects. A collective effort by spectroscopitsts and theoreticians to investigate the diatomic molecule platinum fluoride, PtF, has included research such as developing potential energy diagrams and performing analyses on rotational transitions with microwave spectroscopy. One group observed electronic transitions of PtF using laser vaporization/reaction with jet free expansion and laser induced spectroscopy. A highly effective method for observing and analyzing electronic transitions of small, metal-containing molecules like …

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An Examination Of Factors Influencing Small Proton Chemical Shift Differences In Nitrogen-Substituted Monodeuterated Methyl Groups, Stuart J. Elliott, O. Maduka Ogba, Lynda J. Brown, Daniel J. O'Leary Sep 2021

An Examination Of Factors Influencing Small Proton Chemical Shift Differences In Nitrogen-Substituted Monodeuterated Methyl Groups, Stuart J. Elliott, O. Maduka Ogba, Lynda J. Brown, Daniel J. O'Leary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Monodeuterated methyl groups have previously been demonstrated to provide access to long-lived nuclear spin states. This is possible when the CH2 D rotamers have sufficiently different populations and the local environment is chiral, which foments a non-negligible isotropic chemical shift difference between the two CH2 D protons. In this article, the focus is on the N-CH2 D group of N-CH2 D-2-methylpiperidine and other suitable CH2 D piperidine derivatives. We used a combined experimental and computational approach to investigate how rotameric symmetry breaking leads to a 1H CH2 D chemical shift …

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Automated Code Engine For Tensor Hypercontraction: Derivation, Optimization And Implementation Of Rank-Reduced Coupled Cluster Theories, Yao Zhao Sep 2021

Automated Code Engine For Tensor Hypercontraction: Derivation, Optimization And Implementation Of Rank-Reduced Coupled Cluster Theories, Yao Zhao

Dissertations, Theses, and Capstone Projects

The ultimate goal of electronic structure theory is solving the electronic Schr¨odinger Equation. However, even accurate approximations of solving Schr¨odinger Equation, such as high order coupled cluster theories, require computational efforts that are too demanding to be applied on large chemical systems. This thesis tackles the problem of curse of dimensionality: how to reduce the time complexity of high-accuracy coupled cluster methods in order to accelerate computations of molecular energy. On one hand, we believe that low-rank approximation (i.e. Tensor HyperContraction) of high-order tensors appearing in coupled cluster theory is a promising way to achieve rank-reduced coupled cluster theory. On …

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Modeling Vitexin And Isovitexin Flavones As Corrosion Inhibitors For Aluminium Metal, Abdullahi Muhammad Ayuba, Umaru Umar Aug 2021

Modeling Vitexin And Isovitexin Flavones As Corrosion Inhibitors For Aluminium Metal, Abdullahi Muhammad Ayuba, Umaru Umar

Karbala International Journal of Modern Science

Theoretically, the aluminium corrosion inhibitive performance of vitexin (VTX) and isovitexin (SVT) were evaluated with a view of establishing the mechanism of the inhibition process. Calculations which include the consideration of several global descriptors were studied to describe and correlate the reactivity of the molecules with the computed descriptors. First and second-order condensed Fukui functions were employed to analyze local reactivity parameters, while simulations involving the adsorbed molecules on Al (1 1 0) surface were conducted through quench dynamic simulations and the mechanism of physical adsorption was established with SVT relatively been a better inhibitor on Al surface than VTX.

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Investigating The Proton Transfer Dynamics And Vibrational Spectrum Of Hydrogen Oxalate Using Driven Molecular Dynamics Simulations, Martina Kaledin, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Dalton Boutwell, Martina Kaledin Aug 2021

Investigating The Proton Transfer Dynamics And Vibrational Spectrum Of Hydrogen Oxalate Using Driven Molecular Dynamics Simulations, Martina Kaledin, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Dalton Boutwell, Martina Kaledin

Symposium of Student Scholars

In this computational chemistry work, we describe ab initio calculations and assignment of infrared (IR) spectra of an intramolecular H-bonding system hydrogen oxalate, C2O4H–. The mechanism and dynamics of proton transfer are of fundamental importance in chemistry and biology. In C2O4H–, proton transfer occurs along the non-linear path. Previous experimental studies are signaling very strong coupling between OH stretch mode and low frequency motions. We calculated IR spectra at 300 K using the direct molecular dynamics (MD) method at the MP2/ aug-cc-pVDZ level of theory and assigned the …

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Molecular Vibrations Of Symmetric Molecules: Raman Scattering Driven Molecular Dynamics Method, Martina Kaledin, Dominick Pierre-Jacques, Ciara Tyler, Jason Dyke Aug 2021

Molecular Vibrations Of Symmetric Molecules: Raman Scattering Driven Molecular Dynamics Method, Martina Kaledin, Dominick Pierre-Jacques, Ciara Tyler, Jason Dyke

Symposium of Student Scholars

This project focuses on developing a novel computational technique to study molecular vibrations through infrared (IR) and Raman scattering Driven Molecular Dynamics (DMD) method. While the main criterion for IR absorption is a net change in the dipole moment in a molecule as it vibrates, presently we wish to predict and analyze vibrational spectra to study symmetric vibrational modes that are IR inactive or weakly active while strongly Raman active. A newly developed method was tested on CO2, H2O, CH4, and C20 molecules. Students optimized the molecular structures, obtained vibrational frequencies, and IR …

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Probing Structure And Energetics Of Proton-Bound Complexes N2…Hco+ And N2h+…Oc Using Computational Chemistry Methods, Antonio Barrios, Dalton Boutwell, Onyi Okere, Monique Olocha, Oluwaseun Omodemi, Alexander Toledo, Antonio Barrios Aug 2021

Probing Structure And Energetics Of Proton-Bound Complexes N2…Hco+ And N2h+…Oc Using Computational Chemistry Methods, Antonio Barrios, Dalton Boutwell, Onyi Okere, Monique Olocha, Oluwaseun Omodemi, Alexander Toledo, Antonio Barrios

Symposium of Student Scholars

N2…HCO+ and N2H+…OC are predicted to exist in interstellar clouds. These complexes involve HCO+ and N2H+ fragments that are bound to N2 and CO, respectively using hydrogen-bonded interaction. The reason these molecules are important is that the existence of nitrogen can be measured indirectly through ion-molecular complexes studied in this work. The measured vibrational spectra of molecules is an excellent way to characterize and detect molecules. We used B3LYP, MP2, and CCSD(T) computational methods to predict the structure and vibrational frequencies of N2…HCO+ and N …

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Theoretical Study On The Isomerization And Detection Of N2h+…Oc Complex In Interstellar Clouds, Dalton Boutwell, Martina Kaledin Aug 2021

Theoretical Study On The Isomerization And Detection Of N2h+…Oc Complex In Interstellar Clouds, Dalton Boutwell, Martina Kaledin

Symposium of Student Scholars

In this study, we characterize N2H+…OC linear complex using Driven Molecular Dynamics (DMD) and Vibrational Self-Consistent Field Theory (VSCF) methods due to its relevance in astrochemistry. A central challenge is the detection of the molecular complex in interstellar media (ISM). Computational chemistry approaches can predict vibrational spectra, hence facilitate prediction of its existence and stability in the ISM. N2H+…OC involves the proton transfer process via hydrogen bonding interaction. Proton motion is highly anharmonic, therefore facing a significant challenge to characterize it accurately. Quantum mechanical variational methods are popular among many theoretical chemists …

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Elucidation Of The Combination Bands And Anharmonic Features In The Vibrational Spectra Of C2o4h- And C2o4d- With Driven Classical Trajectories, Dalton Boutwell, Martina Kaledin Aug 2021

Elucidation Of The Combination Bands And Anharmonic Features In The Vibrational Spectra Of C2o4h- And C2o4d- With Driven Classical Trajectories, Dalton Boutwell, Martina Kaledin

Symposium of Student Scholars

Hydrogen bonds are strong electrostatic interactions characterized by the anharmonic shift of vibrational modes of atoms involved with this intramolecular force. The low energy barrier of the H+ transfer in hydrogen oxalate (C2O4H-), predicted to be ~2.98 kcal/mol at the MP2/aVDZ level of theory, allows for rapid proton exchange in the system and confounds the experimental vibrational spectrum of the molecule with broad spectral features in the O-H stretching region. The molecule is planar and exhibits several torsional motions among some of its lower frequency fundamental vibrational transitions. Because H-bonding and torsional motions …

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Model Calculations Of H/D Isotope Substitution In Hydrogen Oxalate Anion Using The Normal Mode Analysis, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Martina Kaledin Aug 2021

Model Calculations Of H/D Isotope Substitution In Hydrogen Oxalate Anion Using The Normal Mode Analysis, Dominick Pierre-Jacques, Olivia Cochran, Dayana Salazar, Martina Kaledin

Symposium of Student Scholars

In this computational chemistry work, we describe ab initio calculations and assignment of infrared (IR) spectra of an intramolecular H-bonding system hydrogen oxalate, C2O4H–. The study of H/D isotope effects can provide useful information on a proton’s location inside a non-linear pathway. In C2O4H–, a normal mode analysis was performed at the MP2/aug-cc-pVDZ and B3LYP/aug-cc-pVDZ levels of theory. Previous experimental studies suggest a frequency shift ~1000 cm-1 for the OH stretch mode upon the H/D isotopic substitution. Isotope calculations resulted in a shift of 842 cm-1 …

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Dft Study Of NiM@Pt1AuN-M-1 (N=19, 38, 55, 79; M = 1, 6, 13, 19) Core-Shell Orr Catalyst, Wen-Jie Li, Dong-Xu Tian, Hong Du, Xi-Qiang Yan Aug 2021

Dft Study Of NiM@Pt1AuN-M-1 (N=19, 38, 55, 79; M = 1, 6, 13, 19) Core-Shell Orr Catalyst, Wen-Jie Li, Dong-Xu Tian, Hong Du, Xi-Qiang Yan

Journal of Electrochemistry

The slow kinetics of oxygen reduction reaction (ORR) limits the performance of low temperature fuel cells. Thus, it needs to design effective catalysts with low cost. Core-shell clusters (CSNCs) show promising activity because of their size-dependent geometric and electronic effects. The ORR activity trend of Nim@Pt1Aun-m-1(n = 19, 38, 55, 79; m = 1, 6, 13, 19) was studied using the GGA-PBE-PAW methods. The adsorption configurations of *O, *OH and *OOH were optimized and the reaction free energies of four proton electron (H+ + e-) transfer steps …

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One-Pot Synthesis Of Fe2O3@Fe-N-C Oxygen Reduction Electrocatalyst And Its Performance For Zinc-Air Battery, Hua Lin, Yi-Jin Wu, Jun-Tao Li, Yao Zhou Aug 2021

One-Pot Synthesis Of Fe2O3@Fe-N-C Oxygen Reduction Electrocatalyst And Its Performance For Zinc-Air Battery, Hua Lin, Yi-Jin Wu, Jun-Tao Li, Yao Zhou

Journal of Electrochemistry

Oxygen reduction reaction (ORR) plays a profound role in determining cathode performance in metal-air batteries and fuel cells. Owing to its inherently sluggish kinetics, high-performance ORR catalysts which favors the scissoring of O-O bond and formation of O-H bond are a requisite. In this regard, Pt has been explored as the most efficient ORR electrocatalysts. Nevertheless, due to its expensiveness, the usage of Pt catalysts represents one of the major sources of cost in those energy conversion devices. Thus, the development of alternative ORR electrocatalysts with minimized Pt utilization has been widely pursued over the past few decades. Metal-nitrogen-carbon catalysts …

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Study On Mxene-Carbon Black/Sulfur Composite In Integrated Electrode Of Lithium-Sulfur Batteries, Ye-Peng Fan, Ye-Qiang Luo, Pei-Kang Shen Aug 2021

Study On Mxene-Carbon Black/Sulfur Composite In Integrated Electrode Of Lithium-Sulfur Batteries, Ye-Peng Fan, Ye-Qiang Luo, Pei-Kang Shen

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries are considered as a promising energy storage device due to their ultrahigh theoretical energy density of 2500 Wh·kg-1 and low cost. However, the practical application of Li-S batteries is seriously limited by their low actual energy density, the shuttle effect of polysulfides (LiPSs), and the insulating nature of sulfur and lithium sulfides. Carbon materials have been developed in the design of sulfur hosts due to their adjustable pore structure and high electrical conductivity, but their non-polar surfaces have weak interactions with LiPSs. Herein, MXene-carbon black/sulfur (Ti3C2Tx-CB/S) composites were prepared and …

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Preparation And Electrochemical Evaluation Of Mos2/Graphene Quantum Dots As A Catalyst For Hydrogen Evolution In Microbial Electrolysis Cell, Hong-Yan Dai, Hui-Min Yang, Xian Liu, Xiu-Li Song, Zhen-Hai Liang Aug 2021

Preparation And Electrochemical Evaluation Of Mos2/Graphene Quantum Dots As A Catalyst For Hydrogen Evolution In Microbial Electrolysis Cell, Hong-Yan Dai, Hui-Min Yang, Xian Liu, Xiu-Li Song, Zhen-Hai Liang

Journal of Electrochemistry

Microbial electrolysis cell (MEC) is a relatively new bioelectrochemical technology that produces H2 and meanwhile treats organic wastewater. Cathode hydrogen evolution catalyst plays a key role in MEC. The doping of Graphene Quantum Dots (GQDs) into MoS2 nanosheets can improve the catalytic activity of MoS2 by creating abundant defect sites both in the edge plane and the basal plane, as well as enhancing the electrical conductivity. In this paper, using Na2MoO4 , cysteine and GQDs as raw materials, a series of MoS2/GQDs composites were firstly synthesized via hydrothermal method, and then loaded …

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