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Articles 1 - 30 of 57
Full-Text Articles in Computational Chemistry
Confirmation Of Anomalous-Heat Report, Steven B. Krivit, Melvin H. Miles
Confirmation Of Anomalous-Heat Report, Steven B. Krivit, Melvin H. Miles
Journal of Electrochemistry
This study identifies, for the first time, critical calculation errors made by Nathan Lewis and his co-authors, in their study presented on May 1, 1989, at the American Physical Society meeting in Baltimore, Maryland. Lewis et al. analysed calorimetrically measured heat results in nine experiments reported by Martin Fleischmann and his co-authors. According to the Lewis et al. analysis, each of the experiments, where calculated for no recombination, showed anomalous power losses. When we used the same raw data, our corrected calculations indicate that each experiment showed anomalous power gains. As such, these data suggest the possibility of a new, …
Automated Workflow For Redox Potentials And Acidity Constants Calculations From Machine Learning Molecular Dynamics, Feng Wang, Jun Cheng
Automated Workflow For Redox Potentials And Acidity Constants Calculations From Machine Learning Molecular Dynamics, Feng Wang, Jun Cheng
Journal of Electrochemistry
Redox potentials and acidity constants are key properties for evaluating the performance of energy materials. To achieve computational design of new generation of energy materials with higher performances, computing redox potentials and acidity constants with computational chemistry have attracted lots of attention. However, many works are done by using implicit solvation models, which is difficult to be applied to complex solvation environments due to hard parameterization. Recently, ab initio molecular dynamics (AIMD) has been applied to investigate real electrolytes with complex solvation. Furthermore, AIMD based free energy calculation methods have been established to calculate these physical chemical properties accurately. However, …
Joint Time-Frequency Analysis: Taking Charge Penetration Depth And Current Spatial Distribution In The Single Pore As An Example, Nan Wang, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jiu-Jun Zhang
Joint Time-Frequency Analysis: Taking Charge Penetration Depth And Current Spatial Distribution In The Single Pore As An Example, Nan Wang, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jiu-Jun Zhang
Journal of Electrochemistry
In recent years, joint time-frequency analysis has once again become a research hotspot. Supercapacitors have high power density and long service life, however, in order to balance between power density and energy density, two key factors need to be considered: (i) the specific surface area of the porous matrix; (ii) the electrolyte accessibility to the intra-pore space of porous carbon matrix. Electrochemical impedance spectra are extensively used to investigate charge penetration ratio and charge storage mechanism in the porous electrode for capacitance energy storage. Furthermore, similar results could be obtained by different methods such as stable-state analysis in the frequency …
Measurements Of Rate Constant For Electrode Reactions, Lian-Huan Han, Jia-Yao Guo, Miao-Miao Cui
Measurements Of Rate Constant For Electrode Reactions, Lian-Huan Han, Jia-Yao Guo, Miao-Miao Cui
Journal of Electrochemistry
Standard electron-transfer rate constant is one of the intrinsic properties for an electrochemical reaction, which is significant in the study of electrode kinetics. It is a key criterion for one to clarify the mechanism and pathway of a specific electrochemical reaction, and to screening and design the electrocatalysts and battery materials. Herein, we will introduce the measuring methods of rate constant for electrode reactions, including polarization curve, rotating disk electrode, ultramicroelectrode, scanning electrochemical microscopy, electrochemical impedance spectroscopy, current step, potential step and cyclic voltammetry, etc., to provide a guide to investigate electrode kinetics for graduate students and researchers in the …
The Top Ten Scientific Questions In Electrochemistry, Chinese Society Of Electrochemistry
The Top Ten Scientific Questions In Electrochemistry, Chinese Society Of Electrochemistry
Journal of Electrochemistry
No abstract provided.
Intelligent Control Based On Bp Artificial Neural Network For Electrochemical Nitrate Removal, Xin-Wan Zhang, Guang-Yuan Meng, Li-Qiang Fang, Ding-Ming Chang, Tong Li, Jin-Wen Hu, Peng Chen, Yong-Di Liu, Le-Hua Zhang
Intelligent Control Based On Bp Artificial Neural Network For Electrochemical Nitrate Removal, Xin-Wan Zhang, Guang-Yuan Meng, Li-Qiang Fang, Ding-Ming Chang, Tong Li, Jin-Wen Hu, Peng Chen, Yong-Di Liu, Le-Hua Zhang
Journal of Electrochemistry
Achieving effective control of parameters in the process of nitrate wastewater treatment is critical to electrochemical water treatment. The powerful nonlinear mapping ability, self-adaptation and self-learning ability of neural network technology can optimize the electrochemical processing. However, there are few researches in this direction. Hence, based on the test data of the electrochemical reduction of nitrate, an electrochemical prediction model was established by using the BP neural network algorithm. Considering the correlation of various parameters in the electrochemical process, the reaction time, initial nitrate nitrogen concentration, pH and current density were determined as the input layer of the BP neural …
Charge-Dependence Of Dissolution/Deposition Energy Barrier On Cu(111) Electrode Surface By Multiscale Simulations, Hang Qiao, Yong Zhu, Sheng Sun, Tong-Yi Zhang
Charge-Dependence Of Dissolution/Deposition Energy Barrier On Cu(111) Electrode Surface By Multiscale Simulations, Hang Qiao, Yong Zhu, Sheng Sun, Tong-Yi Zhang
Journal of Electrochemistry
Behaviors of electrified interface under different applied potentials/charges play the central role in electroplating process and electrochemical corrosion. The mechanism, however, is unclear yet for a surface atom dissolving/depositing from/on an electrode surface under an applied potential. The energy barrier along the reaction path is the key variable. The present work conductes hybrid first-principle/hybrid calculations to study the direct and indirect dissolution/deposition of a Cu atom on perfect/stepped Cu(111) planar electrodes in an electrolyte under different excess charges. Energy profiles present a linear relationship between the energies of the initial/final state and the activation state of different reaction paths under …
Three-Dimensional Two-Phase Cfd Simulation Of Alkaline Electrolyzers, Ling-Yu Gao, Lin Yang, Chen-Hui Wang, Gui-Xuan Shan, Xin-Yi Huo, Meng-Fei Zhang, Wei Li, Jin-Li Zhang
Three-Dimensional Two-Phase Cfd Simulation Of Alkaline Electrolyzers, Ling-Yu Gao, Lin Yang, Chen-Hui Wang, Gui-Xuan Shan, Xin-Yi Huo, Meng-Fei Zhang, Wei Li, Jin-Li Zhang
Journal of Electrochemistry
The structural and operation parameters of the electrolyzer play important roles in the efficiency of alkaline water electrolysis. In this article, a three-dimensional numerical model coupled with the electric field and the Euler-Eulerian k-ε turbulence flow field was first established to simulate accurately the performance of alkaline electrolyzers, based on a compact assembly structure of the industrial alkaline water electrolyzers, especially at current densities higher than 5000 A·m–2. The simulation results are compared with the experimental data to verify the accuracy of the model. Suitable operating conditions for concentration, flow rate and the optimal design method of the …
Application Of Numerical Simulation Method In Periodic Pulse Reverse Electroplating Through Hole, Yuan-Hang Zhang, Mao-Zhong An, Pei-Xia Yang, Jin-Qiu Zhang
Application Of Numerical Simulation Method In Periodic Pulse Reverse Electroplating Through Hole, Yuan-Hang Zhang, Mao-Zhong An, Pei-Xia Yang, Jin-Qiu Zhang
Journal of Electrochemistry
The upgrade of the fifth generation (5G) communication technology increases the number of communication backplane layers and the aspect ratio of through holes on the board, making it more difficult to use traditional direct current deposition for interconnection. Direct current electrodeposition is more prone to uneven coating in the hole, resulting in poor contact between the coating and components, and open circuit. This has a serious impact on the stability of printed circuit board. The periodic pulse reverse plating method can significantly improve the uniformity of high aspect ratio through-hole plating and improve the production quality of through-hole plating through …
Multi-Scale Simulation Revealing The Decomposition Mechanism Of Electrolyte On Lithium Metal Electrode, Yan-Yan Zhang, Yue Liu, Yi-Ming Lu, Pei-Ping Yu, Wen-Xuan Du, Bing-Yun Ma, Miao Xie, Hao Yang, Tao Cheng
Multi-Scale Simulation Revealing The Decomposition Mechanism Of Electrolyte On Lithium Metal Electrode, Yan-Yan Zhang, Yue Liu, Yi-Ming Lu, Pei-Ping Yu, Wen-Xuan Du, Bing-Yun Ma, Miao Xie, Hao Yang, Tao Cheng
Journal of Electrochemistry
Lithium metal is considered as an ideal anode material for next-generation high energy density batteries with its high specific capacity and low electrode potential. However, the high activity of lithium metal can lead to a series of safety issues. For example, lithium metal will continuously react chemically with the electrolyte, forming unstable the solid electrolyte (SEI) films. In addition, lithium dendrites can be formed during cycling, which can puncture the SEI film and cause short circuits in the battery. These drawbacks greatly hinder the commercial application of lithium metal. To solve the above problems, it is important to understand the …
Recent Advances In Electrochemical Kinetics Simulations And Their Applications In Pt-Based Fuel Cells, Ji-Li Li, Ye-Fei Li, Zhi-Pan Liu
Recent Advances In Electrochemical Kinetics Simulations And Their Applications In Pt-Based Fuel Cells, Ji-Li Li, Ye-Fei Li, Zhi-Pan Liu
Journal of Electrochemistry
Theoretical simulations of electrocatalysis are vital for understanding the mechanism of the electrochemical process at the atomic level. It can help to reveal the in-situ structures of electrode surfaces and establish the microscopic mechanism of electrocatalysis, thereby solving the problems such as electrode oxidation and corrosion. However, there are still many problems in the theoretical electrochemical simulations, including the solvation effects, the electric double layer, and the structural transformation of electrodes. Here we review recent advances of theoretical methods in electrochemical modeling, in particular, the double reference approach, the periodic continuum solvation model based on the modified Poisson-Boltzmann …
A Beginners’ Guide To Modelling Of Electric Double Layer Under Equilibrium, Nonequilibrium And Ac Conditions, Lu-Lu Zhang, Chen-Kun Li, Jun Huang
A Beginners’ Guide To Modelling Of Electric Double Layer Under Equilibrium, Nonequilibrium And Ac Conditions, Lu-Lu Zhang, Chen-Kun Li, Jun Huang
Journal of Electrochemistry
In electrochemistry, perhaps also in other time-honored scientific disciplines, knowledge labelled classical usually attracts less attention from beginners, especially those pressured or tempted to quickly jam into research fronts that are labelled, not always aptly, modern. In fact, it is a normal reaction to the burden of history and the stress of today. Against this context, accessible tutorials on classical knowledge are useful, should some realize that taking a step back could be the best way forward. This is the driving force of this article themed at physicochemical modelling of the electric (electrochemical) double layer (EDL). We begin the exposition …
Cyclic Voltammetric Simulations On Batteries With Porous Electrodes, Xue-Fan Cai, Sheng Sun
Cyclic Voltammetric Simulations On Batteries With Porous Electrodes, Xue-Fan Cai, Sheng Sun
Journal of Electrochemistry
Lithium-ion batteries (LIBs) are among the most widely used energy storage devices. Whole-cell modeling and simulations of LIBs can optimize the design of batteries with lower costs and higher speeds. The Pseudo-Two-Dimensional (P2D) electrochemical model is among the most famous whole-cell models and widely applied in LIB simulations. P2D model consists of a series of kinetic equations to model Li+/Li diffusion in working/counter electrodes and electrolytes, which are filled in the porous electrodes and separator, and reactions at the interface of electrolyte and active particles. The traditional applications of P2D model, however, are limited to the cases where the current …
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
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 were calculated. Using …
Structural, Dynamic, Elastic And Electronic Properties Of Anin (A = Li, Na, Mg, Ca): First-Principles Calculations, Xia-Min Huang, Li-Hong Zhang, Shun-Qing Wu, Yong Yang, Zi-Zhong Zhu
Structural, Dynamic, Elastic And Electronic Properties Of Anin (A = Li, Na, Mg, Ca): First-Principles Calculations, Xia-Min Huang, Li-Hong Zhang, Shun-Qing Wu, Yong Yang, Zi-Zhong Zhu
Journal of Electrochemistry
Ternary transition metal nitrides ANiN (A = Li, Na, Mg, Ca) are potential electrode materials for rechargeable batteries. The physical properties, such as the thermodynamic stability, the electronic band gap as well as the elastic stability, are important for their battery applications. Here, comparative studies are performed for the structural, dynamic, elastic and electronic properties of ANiN by the first-principles method. The calculations on the cohesive energy versus unit-cell volume and phonon spectra are employed to determine the most stable structures of ANiN. The calculated elastic constants of the most stable structures indicate that the Born-Huang criterion for the elastic …
Theoretical Study On Electrical Properties Of Molecular Junctions Of Viologen Derivatives, Zhuan-Yun Cai, Jia Liu, Si-Yuan Guan, De-Yin Wu, Zhong-Qun Tian
Theoretical Study On Electrical Properties Of Molecular Junctions Of Viologen Derivatives, Zhuan-Yun Cai, Jia Liu, Si-Yuan Guan, De-Yin Wu, Zhong-Qun Tian
Journal of Electrochemistry
In this paper, the electrical properties of molecular junctions formed N,N′-bis(4-thioalkyl)-4,4′-bipyridinium (viologen) moiety between two gold (Au) electrodes have been investigated by combining density functional theory and non-equilibrium Green’s functional approach. To modulate the viologen molecule to be a cation with one and two positive charges (V+ and V2+), we introduce one and two trifluoroacetic acid ions (TFA-) around the molecule, respectively. The valence states of V+ and V2+ are confirmed by checking Mulliken and NBO charges. Then the relationship between molecular conductance and electronic structures of the neutral state V, the radical state V+ and dication …
Numerical Simulations Of Current And Temperature Distribution Of Symmetrical Double-Cathode Solid Oxide Fuel Cell Stacks Based On The Theory Of Electric-Chemical-Thermal Coupling, Cheng-Rong Yu, Jian-Guo Zhu, Cong-Ying Jiang, Yu-Chen Gu, Ye-Xin Zhou, Zhuo-Bin Li, Rong-Min Wu, Zheng Zhong, Wan-Bing Guan
Numerical Simulations Of Current And Temperature Distribution Of Symmetrical Double-Cathode Solid Oxide Fuel Cell Stacks Based On The Theory Of Electric-Chemical-Thermal Coupling, Cheng-Rong Yu, Jian-Guo Zhu, Cong-Ying Jiang, Yu-Chen Gu, Ye-Xin Zhou, Zhuo-Bin Li, Rong-Min Wu, Zheng Zhong, Wan-Bing Guan
Journal of Electrochemistry
Solid oxide fuel cell (SOFC) is a high-efficient clean conversion device for future energy management. Because of the low antioxidant reduction ability and complex thermal stress, the structure of traditional asymmetrical thin anode-supported planar SOFC is easily to be broken under stack operating conditions. To overcome these defects, a new complete symmetrical SOFC based on double-sided cathodes was developed. To study the influences of gas flow direction and current collection mode on the cell performance inside stack, a numerical model was established by finite element method based on the theory of electro-thermo-chemo multiphysical coupling. By applying this model, the molar …
Pitting Behavior Of Stainless Steel In Simulated Marine Atmosphere Based On Electrochemical Noise, Jun-Hao Deng, Gui Wang, Jie-Zhen Hu, Pei-Chang Deng, Huan-Huan Hu
Pitting Behavior Of Stainless Steel In Simulated Marine Atmosphere Based On Electrochemical Noise, Jun-Hao Deng, Gui Wang, Jie-Zhen Hu, Pei-Chang Deng, Huan-Huan Hu
Journal of Electrochemistry
A measurement system for detecting the atmospheric corrosion of stainless steels was built based on electrochemical noise technology. The electrochemical noise data have been collected for 304 stainless steels which were exposed to the simulated marine atmospheric environment. The pitting behaviors of 304 stainless steels were studied by analyzing the electrochemical noise results with the time domain spectrogram, statistic, frequency domain spectrogram and shot noise theory. Meanwhile, potentiodynamic polarization and morphological analysis were also used as assistant measurements. It has shown that the 304 stainless steel in the whole wet-dry cycle could be divided into three stages, including passivation stage, …
Cyclic Voltammetry Coupled With Faradic Adsorption/Desorption Processes: A Finite Element Simulation, Jia-Yao Guo, Duan Chen, Jie Zhang, Dong-Ping Zhan
Cyclic Voltammetry Coupled With Faradic Adsorption/Desorption Processes: A Finite Element Simulation, Jia-Yao Guo, Duan Chen, Jie Zhang, Dong-Ping Zhan
Journal of Electrochemistry
Heterogeneous electron transfer (HET) coupled with Faradic adsorption/desorption is the fundamental processes involved in hydrogen evolution reaction, oxygen reduction reaction, carbon dioxide reduction reaction, and methanol oxidation reaction. However, the electrochemical behaviors of HET coupled with Faradic adsorption/desorption are complicated, and difficult to get the interface reaction kinetics quantitatively. In this paper, finite element method was adopted to simulate the cyclic voltammetric behaviors of HET coupled with Faradic adsorption/desorption processes by using the Fick’s second law and Langmuir isotherm. The cyclic voltammograms when reactant or product adsorbed weakly or strongly were simulated, and they agreed well with the classical results. …
Insight Into The Important Solid/Liquid Double Layer From First-Principles Calculations, Ya-Hui Fang, Zhi-Pan Liu
Insight Into The Important Solid/Liquid Double Layer From First-Principles Calculations, Ya-Hui Fang, Zhi-Pan Liu
Journal of Electrochemistry
Solid/liquid double layer is of fundamental importance in electrochemistry. It has been a challenge and focus to understand the equilibrium and the dynamic phenomena (e.g., chemical reactions) at the electrode/electrolyte double layer in a unified theoretical framework. In recent years, rapid expansion and development have been done in the application of first principles density function theory (DFT) simulation on the double layer. This article reviews the current theoretical methods for electrochemistry modeling, such as reaction center model, thermodynamic method and double reference model. The progress in the computation procedures based on first principles periodic continuum solvation method (DFT/CM-MPB) for obtaining …
Simulation Of Fractal Growth On Metal Wire Electrode, Li-Feng Ding, Pei-Yuan Mao, Jun Cheng, Yu-Lan Niu, Yu-Hao Wen, Wei Chen
Simulation Of Fractal Growth On Metal Wire Electrode, Li-Feng Ding, Pei-Yuan Mao, Jun Cheng, Yu-Lan Niu, Yu-Hao Wen, Wei Chen
Journal of Electrochemistry
During processes of metal electrodepostion, there exist many complex morphological forms such as dendritic growing in the cathode deposited metal edge, which will seriously affect the quality of the electrodeposited product and current efficiency during machining. Investigations on dendritic crystal growing process and morphology could help controlling growth of electrolysis precipitate. In this work, Python and Matlab softwares were used, and the model of parallel electrode electrodeposition was established based on the diffusion-limited aggregation (DLA) model. By analyzing the law of fractal growth at different conditions of the particles number, probability, electrode spacing, the movement step length and orientation drift, …
Dft Study Of Water Assisted Hydrogen Dissociation On Gold Nanoparticles, Jia-Li Chen, Xia-Guang Zhang, De-Yin Wu, Zhong-Qun Tian
Dft Study Of Water Assisted Hydrogen Dissociation On Gold Nanoparticles, Jia-Li Chen, Xia-Guang Zhang, De-Yin Wu, Zhong-Qun Tian
Journal of Electrochemistry
The gold nanoparticles (GNPs) show special activity toward hydrogen (H2) dissociation, comparing with bulk gold. Such activity is significantly affected by the existence of water. To inspect the influence of water on GNPs catalyzed H2 dissociation, we carried out density functional theory (DFT) calculations along the reaction paths for water clusters (H2O)m (m = 1, 2, 3, 7) assisted H2 dissociation on gold clusters (Aunδ, n = 3 ~ 5; δ = 0, 1). Our calculated results show that water benefits to the H2 dissociation. The dissociation mechanism varies …
Numerical Simulation Of Output Performance In Pemfc, Xin Luo, Shi-Zhong Chen, Yu-Hou Wu
Numerical Simulation Of Output Performance In Pemfc, Xin Luo, Shi-Zhong Chen, Yu-Hou Wu
Journal of Electrochemistry
The COMSOL software was used to analyze the output performances in proton exchange membrane fuel cell(PEMFC) under three kinds of flow fields. Under the same operating conditions, the performance differences among single serpentine flow field, interdigitated flow field and mixed flow field are compared, and the causes of the differences in the output performances of PEMFC under three kinds of flow fields were analyzed. The simulation results showed that the output performance of the mixed flow field was the best, the output performance of the interdigitated flow field the second and the output performance of single serpentine flow field the …
Simulation Analysis In Dynamic Performance Of Proton Exchange Membrane Fuel Cell Under Starting Condition, Yan Xiao, Ying-Jie Chang, Wei Zhang, Qiu-Hong Jia
Simulation Analysis In Dynamic Performance Of Proton Exchange Membrane Fuel Cell Under Starting Condition, Yan Xiao, Ying-Jie Chang, Wei Zhang, Qiu-Hong Jia
Journal of Electrochemistry
Based on the equivalent circuit model, by considering both the dynamic gas pressure model and the dynamic heat transfer model, a lumped parameter model is developed. The start process of the fuel cell is simulated by using SIMULINK software. The undershoot of the voltage is observed from the simulation results, and the response time of the voltage is basically the same as that of the fuel cell temperature, which indicates that the temperature has great influence on the dynamic performance of the fuel cell. From the perspective of the temperature, the dynamic responses of the thermodynamic potential, the activation overvoltage, …
Surface Chemical Properties Of Mo2C, W2C, Mo2N And W2N Probed With Co, Co2And O2 Adsorption: A Dft Analysis, Jingyun Ye, Tianyu Zhang, Lingyun Xu, Shuxia Yin, Krishanthi Weerasinghe, Pamela Ubaldo, Ping And Ge Qingfeng He
Surface Chemical Properties Of Mo2C, W2C, Mo2N And W2N Probed With Co, Co2And O2 Adsorption: A Dft Analysis, Jingyun Ye, Tianyu Zhang, Lingyun Xu, Shuxia Yin, Krishanthi Weerasinghe, Pamela Ubaldo, Ping And Ge Qingfeng He
Journal of Electrochemistry
Transition metal carbides and nitrides are attractive materials for electrodes in many electrochemical energy storage and conversion applications. In the present study, we use density functional theory slab calculations to characterize the surface chemical properties of molybdenum (Mo) and tungsten (W) carbides and nitrides, namely, Mo2C, W2C, Mo2N and W2N with the adsorption of CO, CO2 and O2. These probing molecules provide measures of in both acidity/basicity and redox property of for the surfaces of these carbides and nitrides. Our results show that Lewis basic sites were responsible for CO2 …
Electrostatic Interactions Of Water In External Electric Field: Molecular Dynamics Simulations, Qiang Zhu, Zigui Kan, Jing Ma
Electrostatic Interactions Of Water In External Electric Field: Molecular Dynamics Simulations, Qiang Zhu, Zigui Kan, Jing Ma
Journal of Electrochemistry
A series of molecular dynamics simulations with or without external electric field have been carried out for a bulk water with periodic boundary condition. The difference in radial distribution function of interatomic O…O distance is subtle, with and without external electric field, except for the orientation of dipole moments of water molecules. Without the applied external electric field, distribution of the orientation angle of dipole moments is rather broad. The induced local electric field is analyzed as a function of altitude in direction of electric field. The variation of the local induced electric field is increased as the increase of …
Dynamic Simulation Of Oxygen Reduction Reaction In Pt/C Electrode For Proton Exchange Membrane Fuel Cells, Li Shang, Zhou Fen, Chen Lei, Pan Mu
Dynamic Simulation Of Oxygen Reduction Reaction In Pt/C Electrode For Proton Exchange Membrane Fuel Cells, Li Shang, Zhou Fen, Chen Lei, Pan Mu
Journal of Electrochemistry
It is an urgent need to reduce the Pt loading in electrode for practical fuel cell applications worldwide. Herein, we theoretically investigate the oxygen distribution, generated current, and minimum Pt loading of Pt/C electrode for practical applications based on kinetic model of oxygen reduction reaction. The results indicate that with increasing electrode effective thickness to 40 mm, serious concentration polarization is expected for Pt/C electrode. To generate a power density of 1.4 W•cm-2 (2.1A•cm-2 @0.67 V) for fuel cell, the cathode catalyst layer thickness in PEMFC should be as thin as 3 mm. The minimum Pt loading will …
Electrochemical Catalysis: A Dft Study, Li Li, Zi-Dong Wei
Electrochemical Catalysis: A Dft Study, Li Li, Zi-Dong Wei
Journal of Electrochemistry
In this review, we focus on achievements in electro-catalysis based on the density function theory study. The relationships among the electrode potential, electronic structure of catalysts and electro-catalytic activity are summarized in three parts: the adsorption and desorption of species, electron transfer, and stability of catalysts. The electrode potential and the electronic structure (d-band center or Fermi (HOMO) energy) of catalysts significantly influence the formation, adsorption and desorption of surface species on electrode. The electro-catalytic activity can be improved by modulating the electrode potential and electronic structure of catalysts.
Effects Of Oxygen Coverage And Hydrated Proton Model On The Dft Calculation Of Oxygen Reduction Pathways On The Pt(111) Surface, Li-Hui Ou, Sheng-Li Chen
Effects Of Oxygen Coverage And Hydrated Proton Model On The Dft Calculation Of Oxygen Reduction Pathways On The Pt(111) Surface, Li-Hui Ou, Sheng-Li Chen
Journal of Electrochemistry
DFT calculation is used to study various possible steps in the oxygen reduction reaction (ORR), including the adsorption and dissociation process of O2 and the serial protonation process of dissociated products to form H2O on the Pt(111) surface. By using slabs of different sizes, and different numbers of pre-adsorbed oxygen atoms, the coverage effects on the pathways are investigated. The calculated results using different hydrated proton models are also compared. It is shown that the initial step of the ORR is the formation of a protonated end-on chemisorbed state of OOH*, which can transform to an unprotonated …
A Dft Calculation Screening Of Pt-Based Bimetallic Catalysts For Oxygen Reduction, Li-Hui Ou, Sheng-Li Chen
A Dft Calculation Screening Of Pt-Based Bimetallic Catalysts For Oxygen Reduction, Li-Hui Ou, Sheng-Li Chen
Journal of Electrochemistry
Developing Pt-lean catalysts for oxygen reduction reaction (ORR) is the key for large-scale application of proton exchange membrane fuel cell (PEMFC). In this paper, we have proposed a multiple-descriptor strategy for screening efficient and durable ORR alloy catalysts of low Pt content. We argue that an ideal Pt-based bimetallic alloy catalyst for ORR should possess simultaneously negative alloy formation energy, negative surface segregation energy of Pt and a lower oxygen binding ability than pure Pt. By performing detailed DFT calculations on the thermodynamics, surface chemistry and electronic properties of various Pt-M alloys (M refers to non-precious transition metals in the …