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Full-Text Articles in Physical Sciences and Mathematics

Recent Developments In Surface/Interface Modulation And Structure-Performance Relationship Of Cathode Catalysts For Li-Air Batteries, Rui Gao, Jun-Kai Wang, Zhong-Bo Hu, Xiang-Feng Liu Feb 2019

Recent Developments In Surface/Interface Modulation And Structure-Performance Relationship Of Cathode Catalysts For Li-Air Batteries, Rui Gao, Jun-Kai Wang, Zhong-Bo Hu, Xiang-Feng Liu

Journal of Electrochemistry

Lithium-air battery has been considered to be one of the most promising secondary battery systems because of its high energy density. However, the sluggish kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) on the cathode, and the high overpotential, poor cycle stability and low rate capacity have severely blocked the development and application of Li-air battery. One of the effective strategies to alleviate these issues is to develop cathode catalysts for Li-air batteries. The design and development of bifunctional cathode catalysts with high activity and efficiency on both ORR and OER is highly desired for Li-air …


Recent Progress In Key Materials For Room-Temperature Sodium-Ion Batteries, Fan-Fan Wang, Xiao-Bin Liu, Long Chen, Cheng-Cheng Chen, Yong-Chang Liu, Li-Zhen Fan Feb 2019

Recent Progress In Key Materials For Room-Temperature Sodium-Ion Batteries, Fan-Fan Wang, Xiao-Bin Liu, Long Chen, Cheng-Cheng Chen, Yong-Chang Liu, Li-Zhen Fan

Journal of Electrochemistry

Sodium-ion batteries (SIBs) have attracted tremendous attention in large-scale energy storage applications due to their resource advantages. However, Na+ is larger and heavier than Li+, which will limit its reversible reaction with the electrode materials and result in poor electrochemical performance. Thus, developing stable and high-efficiency electrode materials is the key to promoting the practical application of SIBs. Furthermore, the optimization of electrolyte is essential for the construction of high-safety and long-lifespan SIBs. In this review, we mainly summarize the recent advancements of electrode materials and electrolytes for room-temperature SIBs and discuss their challenges and possible resolution strategies. We hope …


Recent Progress In Vanadium-Based Electrode Materials, Meng-Lei Sun, Da-Qi Zhang, Jin-Kui Feng, Jiang-Feng Ni Feb 2019

Recent Progress In Vanadium-Based Electrode Materials, Meng-Lei Sun, Da-Qi Zhang, Jin-Kui Feng, Jiang-Feng Ni

Journal of Electrochemistry

It is an important solution to solve energy storage problems by developing inexpensive and safe lithium-ion and sodium-ion batteries with superior performance. Vanadium-based electrode materials are promising electrode materials because of diversified chemical valences, open structures and high theoretical capacities. In the past few years, vanadium-based electrode materials such as oxides, sulfides, and phosphates have achieved a considerable development in the battery field, It is, therefore, necessary to summarize their recent research progress. In this review, we particularly highlight the key challenges that are facing in the application of vanadium materials, such as low ion diffusion coefficient and poor structural …


Current Status And Prospect Of Battery Configuration In Li-S System, Jia-Hang Chen, Hui-Jun Yang, Cheng Guo, Jiu-Lin Wang Feb 2019

Current Status And Prospect Of Battery Configuration In Li-S System, Jia-Hang Chen, Hui-Jun Yang, Cheng Guo, Jiu-Lin Wang

Journal of Electrochemistry

Commercial lithium-ion batteries (LIBs) are incapable of satisfying the increasing demand for emerging electronic devices due to their limited energy density. Among the next-generation batteries, lithium-sulfur (Li-S) batteries are becoming a promising energy-storage system due to their high theoretical energy density and natural abundance of sulfur. However, the shuttle of soluble polysulfide intermediates between two electrodes, as well as the problem on Li metal anode,lower the utilization of active material and lead to the loss of specific capacity and rapid capacity fading. All the above challenges limit the further application of Li-S batteries. Recently, various novel battery configurations have been …


Ni/Mn3O4/Nimn2O4 Double-Shelled Hollow Spheres Embedded Into Reduced Graphene Oxide As Advanced Anodes For Sodium-Ion Batteries, Chong Yan, Hua-Ri Kou, Bo Yan, Xiao-Jing Liu, De-Jun Li, Xi-Fei Li Feb 2019

Ni/Mn3O4/Nimn2O4 Double-Shelled Hollow Spheres Embedded Into Reduced Graphene Oxide As Advanced Anodes For Sodium-Ion Batteries, Chong Yan, Hua-Ri Kou, Bo Yan, Xiao-Jing Liu, De-Jun Li, Xi-Fei Li

Journal of Electrochemistry

Delicately building the unique nanocomposite with the combination of hollow structure and reduced graphene oxide (rGO) is highly desirable and still remains a great challenge in the field of energy conversion and storage. In this work, Ni/Mn3O4/NiMn2O4 double-shelled hollow spheres coated by rGO (denoted as R-NMN) have been successfully synthetized via one-step rapid solvothermal treatment followed by subsequent annealing for the first time. Served as anodes for sodium ion batteries (SIBs), the R-NMN composite containing 25wt% rGO exhibits a high discharge capacity of 187.8 mAh·g-1 after 100 cycles at 50 mA·g-1 …


Preface On Special Issue Of Next-Generation Secondary Batteries, Zhen Zhou, Quan-Feng Dong Feb 2019

Preface On Special Issue Of Next-Generation Secondary Batteries, Zhen Zhou, Quan-Feng Dong

Journal of Electrochemistry

No abstract provided.


Cvd Preparation And Application Of 3d Graphene In Electrochemical Energy Storage, Yong-Kang Xia, Ming-Yuan Gu, Hong-Guan Yang, Xin-Zhi Yu, Bing-An Lu Feb 2019

Cvd Preparation And Application Of 3d Graphene In Electrochemical Energy Storage, Yong-Kang Xia, Ming-Yuan Gu, Hong-Guan Yang, Xin-Zhi Yu, Bing-An Lu

Journal of Electrochemistry

Three-dimensional (3D) graphene combinations with the excellent intrinsic properties of graphene and the 3D micro/nano porous structures provide a graphene foam with high specific surface area, excellent mechanical strength and fast electron and mass transports. The 3D graphene foam and its composite nanomaterials are widely used in the fields of nano-electronics, energy storage, chemical and biological sensing. The 3D graphene foam prepared by chemical vapor deposition (CVD) method is of high purity and crystallinity. In this review, a brief overview in the CVD preparations of 3D graphene and properties of CVD prepared 3D graphene based nanomaterials in electrochemical energy storage …


Synthesis Of Flower-Like Vanadium Disulfide For Lithium Storage Application, Pan Li, Jian Liu, Wei-Yi Sun, Hai-Xia Li, Zhan-Liang Tao Feb 2019

Synthesis Of Flower-Like Vanadium Disulfide For Lithium Storage Application, Pan Li, Jian Liu, Wei-Yi Sun, Hai-Xia Li, Zhan-Liang Tao

Journal of Electrochemistry

In order to improve the electrochemical properties of vanadium disulfide (VS2) as an electrode material in Li-ion battery, the flower-like VS2 was prepared by a one-step hydrothermal method with the addition of polyethylene glycol 400. The phase and morphology of the product were characterized by using X-ray diffraction and field emission scanning electron microscopy. During the growth process, it was observed that the flower-like VS2 was interspersed with several hexagonal vanadium disulfide nanosheets, which had a high specific surface area and excellent structural stability. The flower-like VS2 was used for the cathode material test in …


A Comparative Study Of Pre-Lithiated Hard Carbon And Soft Carbon As Anodes For Lithium-Ion Capacitors, Zhao Li, Xian-Zhong Sun, Wen-Jie Liu, Xiong Zhang, Kai Wang, Yan-Wei Ma Feb 2019

A Comparative Study Of Pre-Lithiated Hard Carbon And Soft Carbon As Anodes For Lithium-Ion Capacitors, Zhao Li, Xian-Zhong Sun, Wen-Jie Liu, Xiong Zhang, Kai Wang, Yan-Wei Ma

Journal of Electrochemistry

Lithium-ion capacitor (LIC) has emerged to be one of the most promising electrochemical energy storage devices. Presently, activated carbon (AC) is the mostly used cathode material for LIC. Nevertheless, various carbonaceous materials can be used as anode materials, such as hard carbon (HC) and soft carbon (SC). Therefore, HC and SC with different structural and electrochemical characteristics have been investigated as the anode materials of LICs in this work. Compared with the HC electrode, the SC electrode showed higher electronic conductivity and reversible capacity. The rate capabilities of the two carbonaceous materials as a function of coating thickness have been …


Applications Of Advanced Imaging Technologies For Critical Issues Of All-Solid-State Lithium Battery Studies, Yi-Bo Zhao, Hui-Hui Liu, Song-Liang Chen, Shou-Hang Bo Feb 2019

Applications Of Advanced Imaging Technologies For Critical Issues Of All-Solid-State Lithium Battery Studies, Yi-Bo Zhao, Hui-Hui Liu, Song-Liang Chen, Shou-Hang Bo

Journal of Electrochemistry

All-solid-state lithium batteries have attracted much attention for their high energy density and good safety. To increase their efficiency and prolong their service life, it is necessary to achieve high ion conductivity at the electrode/electrolyte interface and in the electrolyte, as well as to eliminate dendrites growth in the battery. Based on the critical requirements outlined above, this paper discusses the applications of advanced imaging technologies in relevant studies. Recent progresses in investigations of all-solid-state lithium batteries by imaging techniques including electron microscopy, scanning probe microscopy, X-ray tomography, magnetic resonance imaging and optical microscopy are summarized.


Recent Progress On Tio2-Based Anode Materials For Sodium-Ion Batteries, Si-Tian Lian, Jian-Shuai Lv, Qiang Yu, Guang-Wu Hu, Zhuo Chen, Liang Zhou, Li-Qiang Mai Feb 2019

Recent Progress On Tio2-Based Anode Materials For Sodium-Ion Batteries, Si-Tian Lian, Jian-Shuai Lv, Qiang Yu, Guang-Wu Hu, Zhuo Chen, Liang Zhou, Li-Qiang Mai

Journal of Electrochemistry

Titanium dioxide (TiO2) represents a stable, low-cost, and nontoxic anode material for sodium-ion batteries (SIBs). However, the low electrical conductivity limits its electrochemical activity (specific capacity) and rate capability, hindering its widespread applications. In this article, we show that different crystal forms of TiO2 have different pore structures, resulting in the distinct sodium storage capacities. Accordingly, the article introduces how TiO2 microstructures influence sodium storage. The nanoparticle structure can improve the rate performance of the material due to its short ion diffusion distance, and the internal cavity of the hollow structure is beneficial to cycle stability. …


A Review Of Proton Exchange Membrane Fuel Cell Catalyst Layer By Electrospinning, Yong Liu, Han Ding, De-Chun Si, Jie Peng, Jian-Bo Zhang Dec 2018

A Review Of Proton Exchange Membrane Fuel Cell Catalyst Layer By Electrospinning, Yong Liu, Han Ding, De-Chun Si, Jie Peng, Jian-Bo Zhang

Journal of Electrochemistry

The limitation of catalyst layer for proton exchange membrane fuel cell (PEMFC) in cost, durability and performance constitutes the bottleneck for the commercialization of fuel cell vehicles. Electrospun catalyst layer, with high catalyst utilization, increased triple phase boundary (TPB) and triple phase channel (TPC), has been developed by many researchers. This paper reviews the research progress in the electrospun catalyst layer for PEMFC, combined with the author’s work. Firstly, the development progress of catalyst layer is summarized, and the catalyst layer is classified and analyzed based on its fabrication method and structure character. Next, the fabrication process, physical property characterization, …


Fuel Cell Performance Curve After Mea Optimization Structural Optimization Of Low Pt Membrane Electrode Assembly, Yan Rao, Shang Li, Fen Zhou, Tian Tian, Qing Zhong, Zhao-Hui Wan, Jin-Ting Tan, Mu Pan Dec 2018

Fuel Cell Performance Curve After Mea Optimization Structural Optimization Of Low Pt Membrane Electrode Assembly, Yan Rao, Shang Li, Fen Zhou, Tian Tian, Qing Zhong, Zhao-Hui Wan, Jin-Ting Tan, Mu Pan

Journal of Electrochemistry

Membrane electrode assemblies (MEAs) are the key component of proton exchange membrane fuel cell. For a long time, much attention has been paid to develop MEA technology. At present, the research, development and industrialization of fuel cell has entered a new era. More strict requirements for MEA, especially for the reduction of Pt loading with a challenging target of 0.125 mg·W-1 have to be met. In this paper, the performance losses under low Pt loading are analyzed in terms of activation polarization, ohm polarization and mass-transfer polarization. It is proposed that research should be focused on the activity of …


Progress Of Self-Humidifying Membrane Electrode Assembly For Low Temperature Proton Exchange Membrane Fuel Cell, Bin Chi, Yue-Kun Ye, Shi-Jie Jiang, Shi-Jun Liao Dec 2018

Progress Of Self-Humidifying Membrane Electrode Assembly For Low Temperature Proton Exchange Membrane Fuel Cell, Bin Chi, Yue-Kun Ye, Shi-Jie Jiang, Shi-Jun Liao

Journal of Electrochemistry

The self/non-humidification membrane electrode assembly(SH-MEA)is an important pathway towards the self- humidification fuel cell and plays a crucial role for the large scale commercialization of low temperature proton exchange membrane fuel cell (LT-PEMFC), because it not only can reduce the volume and complexity of fuel cell system, resulting in the decrease of the cost, but also can improve the output power density of the fuel cell system. Currently, the researches on the self-humidifying MEA of LT-PEMFC mainly focus on three aspects: the preparation of self-humidification proton exchange membrane, the construction of self-humidification catalyst layer, and the construction of composite self-humidifying …


Special Issue In Honor Of Professor Baolian Yi On His 80th Birthday, Society Of Electrochemistry Chinese Dec 2018

Special Issue In Honor Of Professor Baolian Yi On His 80th Birthday, Society Of Electrochemistry Chinese

Journal of Electrochemistry

No abstract provided.


The Pilot Application Of Electrochemical Impedance Spectroscopy On Dynamic Proton Exchange Membrane Fuel Cell, Jian-Wei Guo, Jian-Long Wang Dec 2018

The Pilot Application Of Electrochemical Impedance Spectroscopy On Dynamic Proton Exchange Membrane Fuel Cell, Jian-Wei Guo, Jian-Long Wang

Journal of Electrochemistry

By analyzing Electrochemical Impedance Spectroscopy (EIS) in applications of dynamic proton exchange membrane fuel cell (PEMFC), bottlenecks which restrict EIS tool development have been pointed out in this paper. Though the high-frequency resistance in EIS is largely accepted as cell inner-resistance, this can only be applied for cell with low current. The low-frequency resistance is difficult to be realized due to its relation with mass transfer. Furthermore, the improved Randles equivalent circuits are built up preliminarily, thus, penetrating into studies for mass transfer reaction, cell operation/degeneration, and high temperature fuel cell. Inspiringly, EIS is becoming an analyzing tool for stack …


Fuel Cells Reactor For Chemicals And Electric Energy Cogeneration, Zhi-Lin Heng, Xiao-Zi Yuan, Yi-Mei Yin, Zi-Feng Ma Dec 2018

Fuel Cells Reactor For Chemicals And Electric Energy Cogeneration, Zhi-Lin Heng, Xiao-Zi Yuan, Yi-Mei Yin, Zi-Feng Ma

Journal of Electrochemistry

As an energy conversion device, fuel cells can efficiently convert chemical energy into electrical energy. With the developing of technology, it is used as a reactor to conduct the synthesis of high value-added chemicals while generating electrical energy. Having benefits such as mild reaction conditions, controllability of the reaction process, high selectivity of the product, as well as high efficiency of energy utilization, it is widely used in many fields such as preparation of high value-added industrial products, gas separation, water treatment, etc. This paper introduces the current trends and statuses of fuel cell reactors in the cogeneration of chemicals …


Fe-N Doped Hollow Carbon Nanospheres Linked By Carbon Nanotubes For Oxygen Reduction Reaction, Ya-Lin Zhang, Chi Chen, Liang-Liang Zou, Zhi-Qing Zou, Hui Yang Dec 2018

Fe-N Doped Hollow Carbon Nanospheres Linked By Carbon Nanotubes For Oxygen Reduction Reaction, Ya-Lin Zhang, Chi Chen, Liang-Liang Zou, Zhi-Qing Zou, Hui Yang

Journal of Electrochemistry

The development of non-precious metal catalysts for oxygen reduction reaction (ORR) is essential for large-scale application of proton exchange membrane fuel cells. Herein, we present the in situ formed Fe-N doped hollow carbon nanospheres linked by carbon nanotubes composite, synthesized by using ZIF-8 as sacrificed template to form polydopamine (PDA) hollow nanospheres, followed by complexing with FeCl3, high temperature heat-treatment and NH3-etching. ZIF-8 was gradually decomposed simultaneously with PDA coating due to the loss of Zn2+ grabbed by PDA. NH3 etching resulted in the improved surface area, while the reducibility of NH3 resulted in …


Voltage Distribution Of Self-Humidifying Air-Cooled Pemfc, Kai-Feng Tan, Wei-Rong Chen, Ming Han, Xue-Xia Zhang Dec 2018

Voltage Distribution Of Self-Humidifying Air-Cooled Pemfc, Kai-Feng Tan, Wei-Rong Chen, Ming Han, Xue-Xia Zhang

Journal of Electrochemistry

In this work, the self-adaptive characteristics of self-humidifying air-cooled PEMFC stack was investigated. The performance and the unit-cell voltage distribution of the stack were measured and analyzed through the unit-cell I-V curve fitting. The operating conditions for this experimental study were set as follows: hydrogen pressure at the anode was 2 bar, the fan power used for the reactant oxygen feed and stack cooling was at 0.3 W, and the duration and time gap of water purged from hydrogen chamber were 1 s and 10 s, respectively. The experimental results showed that the self-humidifying air-cooled PEMFC stack used for this …


Morphological Control Of Ptcu2 Octahedron And Oxygen Reduction Electrocatalytic Performance Of Ptcu For Fuel Cell, Long-Sheng Cao, Lei Wan, Zhi-Gang Shao, Hong-Mei Yu, Ming Hou, Bao-Lian Yi Dec 2018

Morphological Control Of Ptcu2 Octahedron And Oxygen Reduction Electrocatalytic Performance Of Ptcu For Fuel Cell, Long-Sheng Cao, Lei Wan, Zhi-Gang Shao, Hong-Mei Yu, Ming Hou, Bao-Lian Yi

Journal of Electrochemistry

Platinum acetylacetonate (Pt(acac)2) and copper acetylacetonate (Cu(acac)2) were co-reduced to prepare PtCu2 octahedron alloy catalyst in N,N-dimethylformamiade by solvothermal method. The PtCu2 showed lattice compression, and high ratio of non-oxidized Pt with high electronic binding energy. All those structural features contributed to weak adsorption strength of oxygen species on Pt and lower d-band centre position. The influence of structure-directing agent on morphology of PtCu alloy was systematically studied. In the half cell test, as a result of the uniform morphology and regular octahedron of PtCu2 formed, the mass activity and area specific activity …


Durability Performance Of The High-Power Fuel Cell System, Ke-Yong Wang, Wei-Yu Shi, Ren-Fang Wang, Jia Liu, Zhong-Jun Hou Dec 2018

Durability Performance Of The High-Power Fuel Cell System, Ke-Yong Wang, Wei-Yu Shi, Ren-Fang Wang, Jia Liu, Zhong-Jun Hou

Journal of Electrochemistry

Fuel cell durability is the crucial challenge in fuel cell vehicle, and the lifetime of more than 5000 hours is believed to be necessary for vehicle application. Few works on durability test of the full fuel cell system have been reported. In this work, the long lifetime HySYS-30 fuel cell system was developed in Sunrise Power based on the improved MEA durability and system control strategy. The durability performance of the system was investigated under vehicle duty cycle for more than 6000 hours, and only 8.1% performance loss was observed, implying that the durability of HySYS-30 fuel cell system could …


Acid Treated Carbon As Anodic Electrocatalysts Toward Direct Ascorbic Acid Alkaline Membrane Fuel Cells, He-Mu Chen, Chen-Xi Qiu, Yuan-Yuan Cong, Hui-Yuan Liu, Zi-Hui Zhai, Yu-Jiang Song Dec 2018

Acid Treated Carbon As Anodic Electrocatalysts Toward Direct Ascorbic Acid Alkaline Membrane Fuel Cells, He-Mu Chen, Chen-Xi Qiu, Yuan-Yuan Cong, Hui-Yuan Liu, Zi-Hui Zhai, Yu-Jiang Song

Journal of Electrochemistry

In order to improve the hydrophilicity and electrocatalytic activity, commercial carbon black (BP 2000) was subjected to acid treatment to obtain acid-treated carbon (ATC). The generation of rich oxygen-containing groups on the surface of the ATC was proved by X-ray photoelectron spectra (XPS), Fourier transform-infra red spectra (FTIR), thermogravimetric analysis (TG) and contact angle measurement. UV-vis spectra were firstly recorded to calculate activation energy (Ea) of ascorbic acid (AA) chemical oxidation in alkaline conditions by oxygen in air and the Ea value was determined to be 37.1 kJ·mol-1. Additionally, electrochemical impedance spectra (EIS) were used to evaluate unprecedented …


Palladium Adatoms On Gold Nanoparticles As Electrocatalysts For Ethanol Electro-Oxidation In Alkaline Solutions, Hui-Mei Chen, Shang-Qian Zhu, Jia-Le Huang, Min-Hua Shao Dec 2018

Palladium Adatoms On Gold Nanoparticles As Electrocatalysts For Ethanol Electro-Oxidation In Alkaline Solutions, Hui-Mei Chen, Shang-Qian Zhu, Jia-Le Huang, Min-Hua Shao

Journal of Electrochemistry

Palladium (Pd) is a good catalyst for ethanol electro-oxidation in alkaline solutions. The activity of Pd is further improved in this study by modifying the gold (Au) nanoparticles with Pd adatoms using a simple spontaneous deposition process. The Pd overlayer on the Au core (Au@Pd) is un-uniform with some Au atoms exposed to the electrolyte. The activity of Au@Pd/C toward ethanol oxidation reaction (EOR) is much higher than that of Pd/C in an alkaline solution. The peak current density of Au@Pd/C is 4.6 times higher than that of Pd/C with a 100 mV lower onset potential. The enhanced activity may …


Research Progress In Hydrogen Evolution Low Noble/Non-Precious Metal Catalysts Of Water Electrolysis, Yang Li, Zhao-Yan Luo, Jun-Jie Ge, Chang-Peng Liu, Wei Xing Dec 2018

Research Progress In Hydrogen Evolution Low Noble/Non-Precious Metal Catalysts Of Water Electrolysis, Yang Li, Zhao-Yan Luo, Jun-Jie Ge, Chang-Peng Liu, Wei Xing

Journal of Electrochemistry

Hydrogen energy technology with hydrogen as an energy carrier is gaining more and more attention due to its cleanliness and high energy density. Hydrogen fuel cell vehicles have been listed as one of the ultimate energy technologies in the 21st century. Among them, sustainable hydrogen production technology is a necessary prerequisite for the future development of hydrogen energy economy. Electrolyzed water technology driven by renewable resources represents an important way to support the sustainable development of hydrogen energy economy. The development and utilization of high activity, low cost hydrogen evolution catalysts is a key factor in improving the efficiency and …


Recent Progress In Pt-Based Catalysts For Oxygen Reduction Reaction, Jing Li, Xin Feng, Zi-Dong Wei Dec 2018

Recent Progress In Pt-Based Catalysts For Oxygen Reduction Reaction, Jing Li, Xin Feng, Zi-Dong Wei

Journal of Electrochemistry

One major challenge for a large-scale commercialization of the proton-exchange membrane fuel cells (PEMFCs) technologies that enable a shift to ‘zero-emission’ personal transportation, is the expensive and unstable Pt catalysts, which are mainly used to catalyze the sluggish kinetics of the oxygen reduction reaction (ORR) occurred on the air electrode of PEMFCs. Many research works have targets to improve the stability of Pt-based catalysts and to construct Pt/transitional metal alloys with low Pt loading amount. Herein, we provide a minireview for the Pt-based ORR catalysts based on our recent work, which covers a brief background introduction, the stability improvement of …


Constructions Of Noble Metal Nanocrystals With Specific Crystal Facets And High Surface Area, Qiao-Li Chen, Hui-Qi Li, Ya-Qi Jiang, Zhao-Xiong Xie Dec 2018

Constructions Of Noble Metal Nanocrystals With Specific Crystal Facets And High Surface Area, Qiao-Li Chen, Hui-Qi Li, Ya-Qi Jiang, Zhao-Xiong Xie

Journal of Electrochemistry

Noble metal nanocrystals (NCs) have widespread applications in catalysis. Their catalytic performances are strongly related to the surface structures while the atomic utilization efficiency of noble metal is considerably correlated with the surface area. Thus, advantages of both specific surface structure and large surface area are highly required to show off simultaneously so as to optimize the catalytic performance and decrease the usage of noble metal. However, it seems that the two advantages are incompatible with each other in one NC since it is difficult for small NCs to keep their specific facets, while NCs with specific surface structure usually …


Stabilization Strategies Of Pt Catalysts Forproton Exchange Membrane Fuel Cells, Da-Ping He, Shi-Chun Mu Dec 2018

Stabilization Strategies Of Pt Catalysts Forproton Exchange Membrane Fuel Cells, Da-Ping He, Shi-Chun Mu

Journal of Electrochemistry

The low service lifetime of proton exchange membrane fuel cells (PEMFCs) is the main bottleneck for their commercial applications. One of the main factors is that the expensive metal Pt catalyst is easy to degradation under the harsh working environment of PEMFC (such as variable voltage, strong acidity, gas-liquid two-phase flow), which leads to the inevitable decay of the catalytic performance, thus, seriously restricting the lifetime of PEMFC. Therefore, the electrochemical stability of Pt-based electrocatalysts has become an important and hot topic to improve the PEMFC lifetime. In this paper, we review the recent development in enhancing the stability of …


Effects Of So2 In Air On Performance Of Direct Methanol Fuel Cell, Bin Qin, Fen-Ning Jing, Xue-Jing Sun, Gong-Quan Sun, Hai Sun Dec 2018

Effects Of So2 In Air On Performance Of Direct Methanol Fuel Cell, Bin Qin, Fen-Ning Jing, Xue-Jing Sun, Gong-Quan Sun, Hai Sun

Journal of Electrochemistry

Direct methanol fuel cells (DMFC) generally use oxygen as an oxidant. Contaminants such as sulfides and nitrides in the air can affect the performance of the DMFC. In this work, the effects of SO2 on the performance of DMFC were investigated and the mechanism of poisoning was analyzed, by means of constant current discharge curve, polarization performance curve, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In the CV scan, the permeated methanol was oxidized at a low potential to eliminate its effect on the SO2 poisoning behavior test. The results showed that the SO2 poisoning resulted …


Facile Synthesis Of Pt-Cu Alloy Nanodendrites As High-Performance Electrocatalysts For Oxygen Reduction Reaction, Liu-Xuan Luo, Guang-Hua Wei, Shui-Yun Shen, Feng-Juan Zhu, Chang-Chun Ke, Xiao-Hui Yan, Jun-Liang Zhang Dec 2018

Facile Synthesis Of Pt-Cu Alloy Nanodendrites As High-Performance Electrocatalysts For Oxygen Reduction Reaction, Liu-Xuan Luo, Guang-Hua Wei, Shui-Yun Shen, Feng-Juan Zhu, Chang-Chun Ke, Xiao-Hui Yan, Jun-Liang Zhang

Journal of Electrochemistry

Structures and compositions have significant effects on the catalytic properties of nanomaterials. Herein, a facile etching-based method was employed to synthesize Pt-Cu nanodendrites (NDs) with uniform and homogeneous alloy structures for enhancing oxygen reduction reaction (ORR). The formation of dendritic morphology was ascribed to the etching effect caused by the oxidative etchants of the Br-/O2 pair. The atomic ratio of Pt/Cu in Pt-Cu NDs could be easily tuned by altering the ratio of the Pt/Cu precursors, without deteriorating the dendritic morphology. The most active carbon-supported Pt1Cu1 NDs (Pt1Cu1 NDs/C) exhibited the …


Pd/C Catalysts For Co2 Electroreduction To Co:Pd Loading Effect, Dun-Feng Gao, Cheng-Cheng Yan, Guo-Xiong Wang, Xin-He Bao Dec 2018

Pd/C Catalysts For Co2 Electroreduction To Co:Pd Loading Effect, Dun-Feng Gao, Cheng-Cheng Yan, Guo-Xiong Wang, Xin-He Bao

Journal of Electrochemistry

Nanostructured heterogeneous catalysts have been widely used in the electrochemical carbon dioxide (CO2) reduction reaction (CO2RR), which can simultaneously achieve the electrocatalytic conversion of CO2 to fuels and the storage of renewable energy sources. Carbon supported palladium nanoparticles (Pd/C) catalysts have been previously reported to show excellent CO2RR performance. However, the crucial role of the metal loading in supported electrocatalysts has been rarely reported. In this work, we study the Pd loading effect on the structure of Pd/C catalysts as well as their activity and selectivity of CO2RR to CO. The …