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Articles 1051 - 1080 of 4489

Full-Text Articles in Physical Chemistry

Electrochemical Performance Improvement Of Li2Mno3 Cathode Materials By Mgf2 Coating, Du-Dan Wang, Fei Wang, Huan-Huan Zhai, Yu-Peng Li, Na-Chuan Yang, Kang-Hua Chen Apr 2020

Electrochemical Performance Improvement Of Li2Mno3 Cathode Materials By Mgf2 Coating, Du-Dan Wang, Fei Wang, Huan-Huan Zhai, Yu-Peng Li, Na-Chuan Yang, Kang-Hua Chen

Journal of Electrochemistry

Cathode material Li2MnO3 has received more and more attention owing to its high theoretical capacity (459 mAh·g -1). However, the low initial coulombic efficiency and the poor cycle stability hamper its practical application in lithium-ion batteries. Herein, we investigated the crystal structure and electrochemical performance of Li2MnO3 by introducing MgF2 coating layer. The results indicated that the conversion of partial layer Li2MnO3 to spinel phase induced by MgF2 coating could reduce the initial irreversible capacity and improve the first cycle efficiency. The initial coulombic efficiencies of the 0.5wt.%, …

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Syntheses And Properties Of Ta5+ Doped Li7La3Zr2O12, Feng-Feng Peng, Shi-You Li, Tong-Tong Geng, Chun-Lei Li, Shuang-Wei Zeng Apr 2020

Syntheses And Properties Of Ta5+ Doped Li7La3Zr2O12, Feng-Feng Peng, Shi-You Li, Tong-Tong Geng, Chun-Lei Li, Shuang-Wei Zeng

Journal of Electrochemistry

The tantalum ion (Ta 5+) doped garnet-type inorganic solid electrolyte Ta-LLZO was prepared by solid state reaction, and the effect of doping amount on the properties of the materials was investigated. The materials were characterized by X-ray diffraction (XRD), field emission electron scanning microscopy (FESEM) and electrochemical impedance spectroscopy (EIS). And the cycle stability was tested by assembly of LiFePO4//LLZTO//Li all solid lithium battery. The results show that with the increase of Ta 5+ doping amount, the material appeared to form a single cubic phase structure. When the Ta 5+ doping content became 14.09wt.%, x=0.3, the …

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Recent Advances Of Co2 Electrochemical Reduction In Solid Oxide Electrolysis Cells, Yi-Hang Li, Chang-Rong Xia Apr 2020

Recent Advances Of Co2 Electrochemical Reduction In Solid Oxide Electrolysis Cells, Yi-Hang Li, Chang-Rong Xia

Journal of Electrochemistry

Solid oxide electrolysis cells (SOECs) have stimulated wide interests for their promising application in the reduction of CO2 emissions and the storage of renewable energy. Here, the advances made in the development of cathode materials including cermets and perovskite oxides in our research group, are summarized, along with the design of cell configurations. The electrochemical kinetics and performances of cathodes and cells are discussed and analyzed. It is expected that this brief review offers critical insights and useful guidelines for developing superior electrodes and SOECs in the future.

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Cyclic Voltammetry Coupled With Faradic Adsorption/Desorption Processes: A Finite Element Simulation, Jia-Yao Guo, Duan Chen, Jie Zhang, Dong-Ping Zhan Apr 2020

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. …

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Perovskite Catalysts For Fuel Reforming In Sofc:A Review And Perspective, Tong Wei, Jian Li, Li-Chao Jia, Bo Chi, Jian Pu Apr 2020

Perovskite Catalysts For Fuel Reforming In Sofc:A Review And Perspective, Tong Wei, Jian Li, Li-Chao Jia, Bo Chi, Jian Pu

Journal of Electrochemistry

Solid oxide fuel cell (SOFC) is a generating device by electrochemical reaction to transfer the chemical energy of fossil fuels (coal, oil and gas, etc.), the biomass fuel or other hydrocarbon fuels directly into electricity with higher energy conversion efficiency and lower pollution, which is recognized to be efficient green energy technology in the 21st century. However, when hydrocarbons are directly used as fuel, carbon deposition is easy to occur in nickel-based anode, thus, losing electrochemical catalytic activity. Fuel pre-reforming on the outside of the anode is an effective solution, which strongly relies on highly efficient and stable reforming catalysts. …

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Research Progress In Ethane Dehydrogenation To Cogenerate Power And Value-Added Chemicals In Solid Oxide Fuel Cells, Yun Fan, Qi Wang, Jun Li, Jing-Li Luo, Xian-Zhu Fu Apr 2020

Research Progress In Ethane Dehydrogenation To Cogenerate Power And Value-Added Chemicals In Solid Oxide Fuel Cells, Yun Fan, Qi Wang, Jun Li, Jing-Li Luo, Xian-Zhu Fu

Journal of Electrochemistry

Increasing supplies of methane/shale gas have promoted global development of higher value chemicals such as ethylene production by ethane, which dramatically changes the markets of petrochemical industry. Clean and efficient transformation of ethane into higher value chemicals has far-reaching significance. Ethylene production through ethane steam cracking is a relatively matured technology for industrial production. However, the process consumes large amounts of energy and the presence of carbon deposition becomes a serious problem which is difficult to be solved. The cogenerated energy-chemicals solid oxide fuel cells have been widely studied because fuel gas can be converted into high-value chemicals via spontaneous …

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Preparation And Characterization Of Cathode Supported Solid Oxide Fuel Cell, Xiao-Nan Bao, Guang-Jun Zhang, Shao-Rong Wang Apr 2020

Preparation And Characterization Of Cathode Supported Solid Oxide Fuel Cell, Xiao-Nan Bao, Guang-Jun Zhang, Shao-Rong Wang

Journal of Electrochemistry

A site deficient (La0.8Sr0.2)0.95MnO3 (LSM95) powder was synthesized by solid state reaction as a cathode material. The commercial Zr0.9Sc0.1SO1.95 (SSZ) was selected as an electrolyte material and La0.8Sr0.2Cr0.5Mn0.5O3- (LSCrM) was synthesized by sol-gel method as an anode material. Accordingly, single cells of LSCrM-CeO2|SSZ|3YSZ-LSM95 were prepared by tape casting, sintering and impregnation. The single cell test results for LSCrM-CeO2|SSZ|3YSZ-LSM95 with 0.11 g·cm -2 CeO2 and using CH4 as a fuel showed the power …

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Direct Carbon Solid Oxide Fuel Cells, Jiang Liu, Xiao-Min Yan Apr 2020

Direct Carbon Solid Oxide Fuel Cells, Jiang Liu, Xiao-Min Yan

Journal of Electrochemistry

Carbon is richly reserved in coal, biomasses, and many other nature resources. It is usually used as an energy source through oxygen oxidation reaction. The oxidation is generally realized through combustion which causes serious air pollution. Besides, the conversion efficiency of generating electricity through the combustion process is limited by Carnot efficiency. A direct carbon solid oxide fuel cell (DC-SOFC) is a solid oxide fuel cell (SOFC) directly operated with solid carbon as the fuel. It can convert the chemical energy of carbon into electricity with high efficiency. The concentration of produced CO2 from a DC-SOFC is so high …

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Research Progress Of Fuel Electrode In Oxide-Ion Conducting Solid Oxide Electrolysers, Ling-Ting Ye, Kui Xie Apr 2020

Research Progress Of Fuel Electrode In Oxide-Ion Conducting Solid Oxide Electrolysers, Ling-Ting Ye, Kui Xie

Journal of Electrochemistry

Solid oxide electrolysers are now attracting much more attentions because they can efficiently produce fuels by electrolyzing H2O/CO2. In this paper, a comprehensive introduction to the recent progress in the development of fuel electrode (cathode) materials is provided. The advantages, disadvantages and development trend towards various cathode materials are pointed out. The key scientific and technological problems in this field are emphasized.

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Development Status And Prospects Of Hydrogen Production By High Temperature Solid Oxide Electrolysis, Wen-Qiang Zhang, Bo Yu Apr 2020

Development Status And Prospects Of Hydrogen Production By High Temperature Solid Oxide Electrolysis, Wen-Qiang Zhang, Bo Yu

Journal of Electrochemistry

Solid oxide electrolysis cell is an advanced energy conversion device with high efficiency, simplicity, flexibility, and environmental friendliness. It is currently a research hotspot in the international energy field. This paper introduces and analyzes the basic principles, key materials, system components and developments of solid oxidation electrolysis cells. Furthermore, the recent research progresses, challenges and future development directions in solid oxidation electrolysis cells in the field of high-efficiency hydrogen production are summarized and outlined.

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High Temperature Electrochemistry Preface, Jiang Liu Apr 2020

High Temperature Electrochemistry Preface, Jiang Liu

Journal of Electrochemistry

No abstract provided.

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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 Apr 2020

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, …

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Nio@Rgo Supported Palladium And Silver Nanoparticles As Electrocatalysts For Oxygen Reduction Reaction, Shuo Yao, Tai-Zhong Huang, Rizwan Haider, Heng-Yi Fang, Jie-Mei Yu, Zhan-Kun Jiang, Dong Liang, Yue Sun, Xian-Xia Yuan Apr 2020

Nio@Rgo Supported Palladium And Silver Nanoparticles As Electrocatalysts For Oxygen Reduction Reaction, Shuo Yao, Tai-Zhong Huang, Rizwan Haider, Heng-Yi Fang, Jie-Mei Yu, Zhan-Kun Jiang, Dong Liang, Yue Sun, Xian-Xia Yuan

Journal of Electrochemistry

For pervasive applications of fuel cells, highly efficient and economical materials are required to replace Pt-based catalysts for oxygen reduction reaction (ORR). In this study, the NiO@rGO, Pd-NiO@rGO and Ag-NiO@rGO nanoparticles were synthesized, and their catalytic performances toward ORR were investigated. The results revealed that all the three materials were capable of catalyzing ORR, but both the Pd-NiO@rGO and Ag-NiO@rGO showed the better performances compared with the NiO@rGO in terms of the reaction pathway being 4-electron process, the increases of the onset potential and the intermediate yielding rate, as well as the extended stability. Moreover, the effect of Pd modification …

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Construction And Electrochemical Performance Of Garnet-Type Solid Electrolyte/Al-Li Alloy Interface, Jia-Lin Ma, Hong-Chun Wang, Zheng-Liang Gong, Yong Yang Apr 2020

Construction And Electrochemical Performance Of Garnet-Type Solid Electrolyte/Al-Li Alloy Interface, Jia-Lin Ma, Hong-Chun Wang, Zheng-Liang Gong, Yong Yang

Journal of Electrochemistry

Garnet-type solid electrolyte is a newly developed Li ion conductor and promising in the application of all-solid-state batteries. However, Garnet is incompatible with Li anode, which restricts the application of Garnet-type solid batteries. In order to improve the contact between Garnet-type solid electrolyte and Li electrode, a composite anode which contains Al-Li alloy (Al4Li9) was prepared as an electrode. Al-Li alloy has many advantages such as easy preparation, low cost, simple post-treatment and high capacity. Garnet-type Li6.5La3Zr1.75W0.25O12 (LLZWO) was synthesized via solid-state reaction. Garnet solid electrolyte has …

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An Investigation Into The Molecular Dynamics Of The Laser Induced Dissociation Of 2-Bromoethanol, Kirk French Apr 2020

An Investigation Into The Molecular Dynamics Of The Laser Induced Dissociation Of 2-Bromoethanol, Kirk French

Senior Honors Theses

The unimolecular dissociation of 2-bromoethanol is investigated using computational chemistry methods both to test the reliability of the theories and methods of computational chemistry and to explore the internal mechanism of the dissociation. The dissociation of the bromine ion from 2-bromoethanol was experimentally observed in a previous publication by Ratliff et. al. These experimental results were compared in this thesis to computational calculations of their research. The method of TD-B3LYP proved to be inadequate in this venture except for the lowest energies of the most stable conformer of 2-bromoethanol. However, interesting mechanisms were found such as the formation of HBr …

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354— Observation Of Acid Penetration Of Nano-Gold Doped Sol-Gel System, Mir Ali, Eric Koessler Apr 2020

354— Observation Of Acid Penetration Of Nano-Gold Doped Sol-Gel System, Mir Ali, Eric Koessler

GREAT Day Posters

The penetration of the acid into gold doped sol-gel material was measured. The acid penetration speed increased as the nano size increased up from 5 nm to 20 nm. Then there was almost no penetration at 60 nm. The nano dependent rate change was complex and needs to be investigated further. Also, recent new methodology to create the gel showed a significance stability and it took more than a few days to complete the penetration.

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Breakthroughs In Obtaining Qm/Mm Free Energies, Phillip S. Hudson Apr 2020

Breakthroughs In Obtaining Qm/Mm Free Energies, Phillip S. Hudson

USF Tampa Graduate Theses and Dissertations

The computation of free energy is pivotal to understanding the fundamental nature of chemical phenomena. That is, whether a specific molecular outcome occurs spontaneously or is inherently unfavorable. The need to do this with consistent accuracy begs for the use of quantum mechanical (QM) methods. However, techniques for directly computing free energy differences with QM or mixed QM/MM methods are untenable, as the computational expense is quite exorbitant. At present, the most feasible approach for obtaining QM/MM free energies is employing the so-called indirect cycle, which relies on accurately computing free energy differences between low (e.g., molecular mechanical, MM) and …

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Monitoring And Identifying The Rhodamine 6g-Hydroxide Ion Reaction Using In-Situ, Surface-Enhanced Raman Spectroscopy, Ryan Lamb Apr 2020

Monitoring And Identifying The Rhodamine 6g-Hydroxide Ion Reaction Using In-Situ, Surface-Enhanced Raman Spectroscopy, Ryan Lamb

Masters Theses & Specialist Projects

An effective method for monitoring chemical reactions is necessary to better understand their mechanisms and kinetics. Effective reaction monitoring requires a spectroscopy technique with fast data acquisition, high sensitivity, structure-to-spectrum correlation, and low solvent interference. Surface-enhanced Raman spectroscopy (SERS) provides these features, which makes it a valuable tool for monitoring reactions. To obtain the Raman enhancement, metallic nanostructures typically made of silver or gold are aggregated using a salt. The nanoparticles aggregates must then be stabilized using a surfactant to use this method in situ due to eventual nanoparticle precipitation. In this study, gold nanoparticles stabilized with sodium dodecyl sulfate …

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Universality Of Physical And Chemical Critical Effects In Liquid Mixture, Joshua Lang, Xingjian Wang, Pauline Norris Mar 2020

Universality Of Physical And Chemical Critical Effects In Liquid Mixture, Joshua Lang, Xingjian Wang, Pauline Norris

Research Horizons Day Posters

No abstract provided.

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Synthesis And Fabrication Of Trimetallic (Ru-Mn Co) Catalyst Supported On Tio2 And Ni(Oh)2 Thin Films For Photoelectrochemical Applications, Che Mat Ahmad Nazeer Mar 2020

Synthesis And Fabrication Of Trimetallic (Ru-Mn Co) Catalyst Supported On Tio2 And Ni(Oh)2 Thin Films For Photoelectrochemical Applications, Che Mat Ahmad Nazeer

Student Works (2020-2029)

Anatase supported heterogeneous photocatalyst consisting of RuO2, MnO2 and Co3O4 (1:13:13 ratio) was synthesized by precipitation method. The film of the prepared catalyst was fabricated by electrophoretic deposition technique in an aqueous solution of 0.1 mM ammonia and tested for photoelectrocatalytic (PEC) oxidation of methanol in 0.1M KOH under visible light irradiation. The as-prepared photocatalyst was characterized by FTIR, UV–Vis, XRD, Raman spectroscopy, FESEM/EDX, TEM, BET, XPS and TPR. The PEC study by cyclic voltammetry indicates that the oxidation of methanol to CO2 and H2O upon exposure to visible light occurs between 400 and 800 nm. The smaller value of …

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Structures And Electrochemical Properties Of Sn-Cl Co-Doped Li2Mno3 As Positive Materials For Lithium Ion Batteries, Fei Wang, Huan-Huan Zhai, Du-Dan Wang, Yu-Peng Li, Kang-Hua Chen Feb 2020

Structures And Electrochemical Properties Of Sn-Cl Co-Doped Li2Mno3 As Positive Materials For Lithium Ion Batteries, Fei Wang, Huan-Huan Zhai, Du-Dan Wang, Yu-Peng Li, Kang-Hua Chen

Journal of Electrochemistry

Positive material Li2MnO3 shows the highest ratio of lithium to manganese among lithium-rich materials and exhibites the theoretical capacity up to 458 mAh·g-1, making it one of the most promising cathode materials. However, this material has the intrinsic low electrical conductivity and poor cycle stability. In this paper, Li2MnO3, the lithium-rich positive material, was prepared by sol-gel method using acetate as raw material and citric acid as a complexing agent. By using SnC2O4 as a tin source, Sn4+ instead of Mn4+ was introduced to obtain the …

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Preparations Of Nickel-Iron Hydroxide/Sulfide And Their Electrocatalytic Performances For Overall Water Splitting, Hang-Shuo Lu, Xiao-Bo He, Feng-Xiang Yin, Guo-Ru Li Feb 2020

Preparations Of Nickel-Iron Hydroxide/Sulfide And Their Electrocatalytic Performances For Overall Water Splitting, Hang-Shuo Lu, Xiao-Bo He, Feng-Xiang Yin, Guo-Ru Li

Journal of Electrochemistry

The Ni-Fe/Ti oxygen evolution electrode was prepared by electrodeposition on a titanium mesh substrate. Then, the as prepared Ni-Fe/Ti electrode was used to derive the Ni-Fe-S/Ti hydrogen evolution electrode through solid phase sulfuration. The effects of the molar ratio of Ni2+ to Fe3+ in the electrolyte and the amount of thiourea on the structures and electrochemical performances of Ni-Fe/Ti and Ni-Fe-S/Ti electrodes were investigated. The results show that the oxygen evolution performance of Ni-Fe/Ti electrode was first increased and then decreased with the increase of nickel ion content in the electrolyte. The Ni9Fe1/Ti electrode exhibited the best oxygen …

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Electrochemical Impedance Spectroscopy For Electrocatalytic Interfaces And Reactions: Classics Never Die, Jun Huang Feb 2020

Electrochemical Impedance Spectroscopy For Electrocatalytic Interfaces And Reactions: Classics Never Die, Jun Huang

Journal of Electrochemistry

This review article recapitulates electrochemical impedance spectroscopy (EIS) studies in the field of electrocatalysis. The history of this specialized field, ranging from the beginning of the twentieth century to now, is outlined. We then chronicle milestones of the impedance theory. Special emphases are put on the Dolin-Ershler model, the prevailing model for analyzing adsorption impedance data. Afterwards, we narrow into a very specific and fundamental topic, the double-layer capacitance at platinum (Pt) single crystals. We discuss the challenges in experimentation and theoretical understanding thereof. We cast doubts into the validity of using the Dolin-Ershler model to obtain the double-layer capacitance …

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Electrochemical Preparations And Applications Of Nano-Catalysts With High-Index Facets, Chi Xiao, Na Tian, Zhi-You Zhou, Shi-Gang Sun Feb 2020

Electrochemical Preparations And Applications Of Nano-Catalysts With High-Index Facets, Chi Xiao, Na Tian, Zhi-You Zhou, Shi-Gang Sun

Journal of Electrochemistry

The performance of catalysts highly depends on their surface structure and composition. Nanocrystals bounded by high-index facets usually exhibit high catalytic activity due to their high-density low-coordinated step atoms with high reactivity. In this paper, we have reviewed the preparations of noble metals (e.g., Pt, Pd and Rh) nanocatalysts with high-index facets by electrochemical square-wave potential method developed in our group. The square-wave potential method includes a nucleation procedure to generate nuclei, followed by a square-wave potential procedure for a certain period of time for the growth of nuclei into nanocrystals. The formation mechanism of high-index facets is also discussed. …

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Insight Into The Important Solid/Liquid Double Layer From First-Principles Calculations, Ya-Hui Fang, Zhi-Pan Liu Feb 2020

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 …

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Recent Progress In The Mechanistic Understanding Of Co2 Reduction On Copper, Matthew M Sartin, Wei Chen, Fan He, Yan-Xia Chen Feb 2020

Recent Progress In The Mechanistic Understanding Of Co2 Reduction On Copper, Matthew M Sartin, Wei Chen, Fan He, Yan-Xia Chen

Journal of Electrochemistry

In this review, we present the major developments in the understanding of the mechanisms of the electrochemical reduction of CO2 from a historical perspective. Most of the work discussed in this review was carried out at copper electrodes, as this is the only material at which hydrocarbons are produced in reasonable quantities. The emphasis focuses on the differentiation of mechanisms for the generation of C1 and C2 products as well as factors and methods for controlling the product selectivity of CO2 reduction. We have highlighted ambiguities, assumptions, and important methodologies, such as differential electrochemical mass spectrometry and electrochemical …

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Effect Of Nitrogen Content In Catalyst Precursor On Activity Of Fen/C Catalyst For Oxygen Reduction Reaction, Zhi Yang, Ya-Yun Shen, E Zhou, Cheng-Ling Wei, Hao-Li Qin, Juan Tian Feb 2020

Effect Of Nitrogen Content In Catalyst Precursor On Activity Of Fen/C Catalyst For Oxygen Reduction Reaction, Zhi Yang, Ya-Yun Shen, E Zhou, Cheng-Ling Wei, Hao-Li Qin, Juan Tian

Journal of Electrochemistry

Non-noble metal catalysts with high activity and low cost have attracted increasing interest as potential catalysts for oxygen reduction reaction (ORR) to replace Pt-based catalysts. In this paper, the effect of nitrogen content in catalyst precursor on ORR activity of FeN/C catalyst was investigated by X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET) surface area and pore size distribution measurements, transmission electron microscope (TEM), thermogravimetric analysis (TGA), and rotating disk electrode (RDE) techniques. The results show that the most active catalyst was obtained by pyrolysis in argon at 1050 °C with a catalyst precursor containing 20wt% 1,10-phenanthroline, 1wt% Fe and Black Pearl 2000. …

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Challenges In The Activity And Stability Of Pt-Based Catalysts Toward Orr, Tuo Zhao, Er-Gui Luo, Xian Wang, Jun-Jie Ge, Chang-Peng Liu, Wei Xing Feb 2020

Challenges In The Activity And Stability Of Pt-Based Catalysts Toward Orr, Tuo Zhao, Er-Gui Luo, Xian Wang, Jun-Jie Ge, Chang-Peng Liu, Wei Xing

Journal of Electrochemistry

The development of highly efficient oxygen reduction reaction (ORR) catalysts is the key to the commercialization of fuel cells, where the sluggish ORR reaction rate needs to be overcome by adjusting the intermediates adsorption energies on the catalytic surfaces. To-date, platinum (Pt)-based materials are the-state-of-the-art catalysts in terms of both activity and stability in ORR, making them the preferred choice for commercial applications. However, the high cost of Pt-based catalysts limits their widespread use, leading to massive effects paid in reducing Pt loading, improving catalyst activity and stability. This article illustrates the challenges in the ORR reaction and introduces the …

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Research Progresses In Polymeric Proton Exchange Membranes For Fuel Cells, Xu-Po Liu, Yun-Feng Zhang, Shao-Feng Deng, De-Li Wang, Han-Song Cheng Feb 2020

Research Progresses In Polymeric Proton Exchange Membranes For Fuel Cells, Xu-Po Liu, Yun-Feng Zhang, Shao-Feng Deng, De-Li Wang, Han-Song Cheng

Journal of Electrochemistry

Proton exchange membrane (PEM) is one of the key components in PEM fuel cells, which possesses the function of separating the cathode and anode, affording proton transport channels and preventing fuel permeability. The property of PEM significantly influences the performance and service life of fuel cells. Nowadays, the commercially used Nafion membranes have the shortcomings of serious fuel permeability, low proton conductivity at elevated temperature and high price, which limits the rapid development of PEM fuel cells. Therefore, it seems to be urgent to develop novel PEMs with low cost and good comprehensive properties. Polymeric proton exchange membrane is an …

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Lithium Storage Performance Of High Capacity Material Si@CPzs In Lithium Ion Batteries, Qing-Nuan Zhang, Fang-Fang Zhang, Hong-Xia Li, Bing-Jun Yang, Xiao-Cheng Li, Juan Yang Feb 2020

Lithium Storage Performance Of High Capacity Material Si@CPzs In Lithium Ion Batteries, Qing-Nuan Zhang, Fang-Fang Zhang, Hong-Xia Li, Bing-Jun Yang, Xiao-Cheng Li, Juan Yang

Journal of Electrochemistry

Carbon layers with different thicknesses were introduced into the surfaces of silicon (Si) nanoparticles by sol-gel method using poly (cyclotriphosphazene-co-4, 4'-sulfonyldiphenol) as the carbon source. Technologies of X-ray diffraction, thermo-gravimetric analysis, Brunauer-Emmett-Teller and transmission electron microscopy were employed to analyze the structures and components of the as-prepared Si@CPZS composites. Electrochemical performance of Si@CPZS with different carbon thicknesses was studied. The results showed that Si@CPZS with carbon thickness of 10 nm possessed the best performance. Its capacity remained 940 mAh·g-1 after 290 cycles under 500 mA·g-1. As the addictive, the graphite-based anode contained 30% of …

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