Welcome to Visit Journal of Electrochemistry,Today is Share:

Table of Content

    28 August 2018, Volume 24 Issue 4
    Table of Contents
    Table of Contents
    2018, 24(4):  0. 
    Asbtract ( 1206 )   PDF (13995KB) ( 2464 )  
    Related Articles | Metrics
    Acetylcholinesterase Biosensor Platform Based on BP2000 for the Detection of Carbaryl
    ZHANG Ming-han, JIANG Jun-qiao, Ge Jun-jie, XING Wei
    2018, 24(4):  303-308.  doi:10.13208/j.electrochem.171229
    Asbtract ( 976 )   PDF (37651KB) ( 2410 )  
    References | Related Articles | Metrics

    With the purpose of providing a new method for carbaryl (a pesticide) detection, on the basis of the principle that acetylcholinesterase (AChE) activity can be restrained by carbaryl, an AChE biosensor platform based on BP2000 (as a fixation) was constructed by dropping method. As a result, it revealed that AChE immobilized on BP2000 maintained its catalytic activity for acetylcholine (ATCl), and due to the introduction of the BP2000 material, the effective electrochemical surface area of the modified electrode was enlarged. In addition, the electrochemical oxidation at the modified electrode occurred at low potential (0.630 V) accompanied by proton transmission. The AChE biosensor platform based on BP2000 matrix for carbaryl detection was able to reflect a linear response in the range of 2.0 ng·mL-1 ~ 12.5 ng·mL-1 with the detection limit of 3.15 ng·mL-1. At last, this work will provide a simple method and an efficient matrix in establishing an enzyme electrode of enzymatic biosensor platform and enzymatic fuel cell.

    Preparations of Nano-Manganite Loaded Titanium Electocatalytic Membrane Electrode for Phenolic Wastewater Treatment
    LI Le, WANG Hong, MA Rong-hua, HUI Hong-sen, LIANG Xiao-ping, LI Jian-xin
    2018, 24(4):  309-318.  doi:10.13208/j.electrochem.180216
    Asbtract ( 1331 )   PDF (121008KB) ( 2330 )  
    References | Related Articles | Metrics

    Nano-manganese oxide loaded on titanium electrocatalytic membrane electrodes (nano-MnOx/Ti) were synthesized bysol-gel method using porous Ti membrane as a substrate and the manganese acetate as a raw material without releasing NOx. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Field-emission scanning electron microscopy (FESEM) were employed to characterize crystal form, valence state and surface morphology of nano-MnOx, respectively. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) were used to investigate the electrochemical properties of nano-MnOx electrode. The results indicated that the MnOx catalysts consisted of γ-MnO2 and Mn2O3 nanorods with the diameter of 50 nm, which distributed uniformly on the Ti membrane. The electrochemical performance and catalytic performance of the membrane electrode improved obviously after the loading of the catalyst. The formation of chemical bond between Ti and MnOx led a good stability of MnOx/Ti membrane electrode. The electrocatalytic membrane reactor (ECMR) was assmblied by using nanorods the MnOx/Ti membrane as an anode and a stainless steel mesh as a cathode for the phenolic wastewater treatment (10 mmol·L-1). It was found that the COD removal rate of ECMR was up to 95.1% at current density of 0.25 mA·cm-2and residence time of 15 min.

    Highly Crystalline Nickel Borate Nanorods as Oxygen Evolution Reaction Electrocatalysts
    XU Xi,LIU Juan,WU Hua-zong,Jiang Wen-jie
    2018, 24(4):  319-323.  doi:10.13208/j.electrochem.171115
    Asbtract ( 1557 )   PDF (55478KB) ( 2972 )  
    References | Related Articles | Metrics
    Hydrogen energy, a kind of clean and renewable energy, is considered to be the solution to the problems of energy crisis and environmental deterioration. Electrochemical water splitting is an efficient and promising technology for the production of high-purity hydrogen. However, oxygen evolution reaction (OER) at the anode of water electrolyzer limits the efficiency of water splitting due to the high overpotential. Therefore, the challenges still remain for the exploration of highly active, stable and low-cost catalysts with superior activity for OER. Herein, nickel borate nanorods with high crystallinity were prepared via high-temperature calcination. The as-obtained nickel borate nanorods with 2 μm in length and 200 nm in diameter exhibited excellent OER activity in terms of an overpotential of 373 mV at 10 mA·cm-2, even though their capacitance value is extremely low (0.03 mF·cm-2), which could be further improved by coupling with other conductive materials or decreasing the size of nickel borate.
    Hybrid Battery-Capacitor System based on LiTi5O12 Anode and PTPAn Cathode
    SU Xiu-li, DONG Xiao-li, LIU Yao, WANG Yong-gang, YU Ai-shui
    2018, 24(4):  324-331.  doi:10.13208/j.electrochem.171226
    Asbtract ( 1086 )   PDF (60231KB) ( 603 )  
    References | Related Articles | Metrics
    Owing to its high safe, high rate and long life characteristics, lithium titanate (Li4Ti5O12) anode material has attracted extensive attention in recent years, and many efforts are being made to develop the Li4Ti5O12 based high performance hybrid supercapacitors and Li-ion batteries. Herein, we prepared the organic cathode material polytriphenylamine (PTPAn) through chemical oxidation and polymerization of triphenylamine (TPAn), and investigated its charge storage mechanism and electrode kinetics withthe typical electrochemical methods in an organic electrolyte. It was demonstrated that the PTPAn exhibited the reversible capacity of 85 mA·g-1. The charge storage depended on the reversible adsorption/desorption of anion, which is not controlled by the diffusion process, and thus, can be considered as the pseudocapacitive behavior. Then, the PTPAn cathode was coupled with the Li4Ti5O12 anode to form a hybrid capacitor/battery system with high power and improved energy density. Finally, the inherent drawback and the challenge for practical application of such an organic cathode are briefly discussed.
    An Aqueous All-Metal Oxide Asymmetric Supercapacitor with High Gravimetric and Volumetric Energy Densities
    JING Xin, ZHANG Xu, WANG Wei, LANG Jun-wei
    2018, 24(4):  332-343.  doi:10.13208/j.electrochem.180204
    Asbtract ( 1040 )   PDF (129786KB) ( 438 )  
    References | Related Articles | Metrics

    Only with both high gravimetric and high volumetric energy densities, can supercapacitors find more extensive applications.In this paper, by making good use of the interesting nanostructures and the high packing densities of RuO2 (nanoshpheres,1.69 g·cm-3) and Co-Ni oxide (nanoflakes, 2.14 g·cm-3), the RuO2//KOH//Co-Ni oxide all-metal oxide asymmetric supercapacitors with high performance were successfully fabricated, which led to the maximum specific capacitance of 217.5 F·g-1 (412.3 F·cm-3) and specific energy density of 61.8 Wh·kg-1 (121 Wh·L-1) in a cell voltage between 0 and 1.5 V in KOH electrolyte. In addition, the constructed supercapacitor device could retain 87% of the initial specific capacitance even at 5000th cycle with the cell voltage of 1.4 V at a current density of 2 A·g-1 in life cycle test, indicating high electrochemical stability.

    Complex Coordination Silver Electrocrystallization Mechanism on Glassy Carbon Electrode Surface
    HUANG Shuai-shuai, LIU Cheng, JIN Lei, YANG Fang-zu, TIAN Zhong-qun, ZHOU Shao-min
    2018, 24(4):  344-350.  doi:10.13208/j.electrochem.180105
    Asbtract ( 1194 )   PDF (19936KB) ( 383 )  
    References | Related Articles | Metrics

    Cyclic voltammetry and potential step methods were successfully used to study the electrochemical crystallization mechanism of silver deposition on glassy carbon electrode (GCE) in the practical cyanide-free silver plating electrolyte containing composite complexing agents. Scharifker-Hill (SH) theory was used to fitting the experimental data. The results showed that the electrodeposition of silver is a diffusion controlled irreversible electrode process according to three-dimensional instantaneous nucleation mechanism. When the step potential shifted from -750 mV to -825 mV, the peak deposition current Im was increased, while the induced nucleation time tm shortened. The calculated kinetic parameters showed that the diffusion coefficient (D) was basically constant, ranged (7.31 ±0.34) ×10-5 cm2·s-1, and the active nucleation sites density (N0) increased from 3.26 ±105 cm-2 to 10.2±105 cm-2. The morphologies for the initial deposition of Ag verified the three-dimensional instantaneous nucleation mechanism. Increasing the temperature could significantly improve the diffusion ability of the active silver coordination ions in the electrolyte, which shortened the nucleation time and enhanced the active nucleation sites density N0.

    Assemblies and Properties of Asymmetric Supercapacitors Based on WO3/Carbon Cloth
    SHAO Wen-ke, ZHAO Lei, LIU Chao, DONG Yan-ying, ZHU Yuan-jie, WANG Qiu-fan
    2018, 24(4):  351-358.  doi:10.13208/j.electrochem.180124
    Asbtract ( 1458 )   PDF (67821KB) ( 595 )  
    References | Related Articles | Metrics
    The demand for a new generation of flexible, portable, and high-capacity power sources increases rapidly with the development of advanced wearable electronic devices. One dimensional (1D) nanowires structures have been demonstrated as one of the most ideal electrode materials in energy storage systems due to their advantages in both micorstructures and their high surface areas. Here we report a simple process for large-scale fabrication of self-standing composite film electrodes composed of WO3 nanorods on carbon cloth. In order to improve the energy density of supercapacitor, we assembled an asymmetric supercapacitor using WO3 nanorods and activated carbon cloth as positive and negative electrodes, respectively. The scanning electron microscopy (SEM) and X-ray diffraction spectroscopy (XRD) were used to characterize the morphology and structure of the electrode materials, respectively. In addition, cyclic voltammetry (CV), galvanostatic charge-diacharge (GCD) test, and electrochemical impedance spectroscopy (EIS) were employed to study the electrode materials in a three-electrode system. It was found that the WO3 nanorods exhibited attractive electrochemical performance as well as remarkable flexibility with the high areal capacitance of 3347 mF·cm-2 at 5 mA·cm-2. In addition, to improve the electrochemical performance of activated carbon cloth by introducing function groups onto its surface for producing pseudocapacitance and increasing surface area by electrochemically oxidizing CC in the mixed acid solution, it was also shown the high areal capacitance of 1160 mF·cm-2 at 7 mA·cm-2. This method was simpler and more effective compared with the previous strategies for activating carbon materials. The as-fabricated asymmetric supercapacitor based on WO3/carbon cloth exhibited high areal capacitance of 58.96 F·cm-2 at 61.9 mA·cm-2, high energy density of 20.36 mWh·cm-2 at 0.48 W·cm-2 with the operation voltage window expanding to 0 ~ 1.6 V, and excellent lifespan after 3000 cycles. This work opens up a novel, low-cost route to design advanced integrated-array and high performance electrode materials for portable supercapacitor application on a large scale.
    Preparation and Characterization of Self-Supporting Flexible Nitrogen-Doped Carbon Fabric Electrodes
    YANG Bo, JIN Zhi-hang, ZHAO Ya-ping, CAI Zai-sheng
    2018, 24(4):  359-366.  doi:10.13208/j.electrochem.180110
    Asbtract ( 786 )   PDF (117167KB) ( 465 )  
    References | Related Articles | Metrics

    With the wide applications of intelligent wearable devices in various fields, developing a new generation of flexible energy storage devices has become a major challenge for the current technology. As a wide application of wearable flexible substrate, cotton fabric has the advantages over low price, non-toxic and environmental friendly, but the poor conductivity becomes a major problem limiting its development. As a nitrogen-containing conducting polymer, polypyrrole is traditionally used as electrode materials, but poor mechanical performance and cycle stability severely limit its application in electrode materials. In this article, a self-supporting flexible nitrogen-doped carbon fabric electrode was prepared by in situ polymerization-high temperature calcination method using cotton as a substrate and polypyrrole as a nitrogen source. The high temperature carbonization transformed the non-conductive cotton fabric into a good conductive carbon fabric while retaining its original three-dimensional structure and the nitrogen was mixed into carbon materials at the same time. The structure was characterized by Fourier infrared spectroscopy, specific surface area test, scanning electron microscopy and X-ray photoelectron spectroscopy. The results demonstrated that the cotton fiber was uniformly coated by polypyrrole that was subsequently carbonized into nanocarbon, the specific surface area of the obtained nitrogen-doped carbon (N-CT) electrode was 495.0 m2·g-1 and the nitrogen content was 2.26%. The electrochemical performance test showed that the N-CT electrode had a capacitance of 256.2 F·g-1 at a current density of 0.5 A·g-1. The stability test revealed that the capacitance retention was 98.3% and the coulomb effciency was about 98.8% after 5000 charge-discharge cycles. Meanwhile, the N-CT electrode exhibited good flexibility and mechanical properties.

    Electrochemical Performances of Neodymium Doped Lead Dioxide Composite Anode
    WANG Hong-hui, MA Ming-jie, FENG Jie, KANG Huang-ya, HUANG Wen-jie
    2018, 24(4):  367-374.  doi:10.13208/j.electrochem.180411
    Asbtract ( 815 )   PDF (33640KB) ( 332 )  
    References | Related Articles | Metrics

    Neodymium (Nd) doped titanium (Ti)-based lead dioxide (PbO2) composite anode was prepared by electrodeposition. The surface morphologies and crystal structures of the as-prepared anodes were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) technique, respectively. The electrochemical performances of PbO2-Nd anode were studied by electrochemical impedance spectroscopy, linear sweep voltammetry and cyclic voltammetry. Additionally, the electrocatalytic activity and durability of PbO2-Nd anode were investigated through the degradation of simulative refractory organic wastewater of phenol. The results showed that Nd doping made the PbO2 anode surface structure dense and uniform with smaller sized crystal particles, which increased the specific surface area and improved the electrochemical properties of the anode. The surface crystal structures of PbO2 and PbO2-Nd anodes were mainly composed of β-PbO2. Furtheremore, Nd doping improved the crystal purity of β-PbO2, changed the relative abundance of the surface phase and promoted the formation of β(101) crystal plane. Moreover, the PbO2-Nd anode exhibited smaller electrochemical reaction resistance, higher oxygen evolution potential, stronger electron exchange capacity and longer life time than PbO2 anode. Upon electrocatalytic degradation of phenol wastewater with the PbO2-Nd anode for
    3 h, the removal rate of phenol and COD reached 85.7% and 73.8%, respectively. The electrocatalytic activity of the PbO2-Nd anode had no significant attenuation after being used for 6 times. The PbO2-Nd anode possessed better electrocatalytic activity and durability than PbO2 anode.

    Influences of Na-Mn Ratio on Electrochemical Performances and Intercalation-Deintercalation Processes of Sodium Ion in NaxMnO2
    XIE Yong-chun, WANG Cheng, JIANG Fang, YANG Yang, SU Jing, LONG Yun-fei, WEN Yan-xuan
    2018, 24(4):  375-384.  doi:10.13208/j.electrochem.180207
    Asbtract ( 1428 )   PDF (133318KB) ( 711 )  
    References | Related Articles | Metrics
    In this work, NaxMnO2 was synthesized by a solid-state reaction. The influences of Na:Mn ratio on the structure, morphology and electrochemical performance, and sodium ion intercalation/deintercalation processes were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge test. The prepared NaxMnO2 was mainly composed of Na0.7MnO2 and Na0.91MnO2, and the content of Na0.91MnO2 increased with the increase of Na:Mn ratio. However, the activation energy values of surface membrane diffusion, interfacial electrochemical reaction and Na+ diffusion in the bulk material first decreased and then increased with the increase of Na:Mn ratio, while the discharge capability first increasedand then decreased with the increase of Na:Mn ratio. The sample synthesized with the Na:Mn ratio of 0.80 delivered a discharge capacity of 152.8 mAh·g-1 with a capacity retention of 80.6% after 50 cycles at 1C. Even being charged/discharged at 5C, this sample still provided a discharge capacity of 88.3 mAh·g-1, showing good cycle-stability and rate performance. The activation energy values of surface membrane diffusion, interfacial electrochemical reaction and solid-phase diffusion were found to be 68.23, 40.07 and 57.62 kJ·mol-1, respectively.
    Modifications and Electrochemical Properties of Graphite Fluoride
    Zhang Liang, Zhang Hong-mei, Wan Wei-hua, Wei Jun-hua
    2018, 24(4):  385-391.  doi:10.13208/j.electrochem.180131
    Asbtract ( 1134 )   PDF (43438KB) ( 1134 )  
    References | Related Articles | Metrics

    The commercial fluorinated graphite (CFx) was used as the raw material, which was modified by the reduction of hydrazine hydrate (N2H4·H2O). The effects of hydrazine hydrate contents on the electrochemical properties of fluorinated graphite were systematically studied. The crystal phases and electrochemical properties of the modified fluorinated graphite were analyzed by XRD, SEM, EDS, XPS, EIS techniques and constant current discharge measurement. The results showed that the voltage hysteresis response of Lithium-fluorocarbon battery prepared by the modified fluorinated graphite was obviously improved, while the amount of hydrazine hydrate had an important influence on the electrochemical performance of the materials. The H-CFx-2 material had the best overall performance (CFx:C2H6O: N2H4·H2O  was 1:2:1). At 0.1C, the specific capacity of the material reached 794.5 mAh·g-1, the platform voltage was 2.53 V, and the low-wave voltage of the voltage hysteresis was 2.37 V.

    Electrochemical Preparation and Photo-Electro Catalytic Properties of Flexible ZnNi/Al-LDHs/Carbon Fibers Composite
    TIAN Jing-jing, CHEN Tao, BAO Xing-chen, GAO Meng-xu, YU Ye-xiao, PENG Si-yao, JIN Guan-ping
    2018, 24(4):  392-400.  doi:10.13208/j.electrochem.170726
    Asbtract ( 1128 )   PDF (61667KB) ( 496 )  
    References | Related Articles | Metrics
    In this work, a promising flexible composite consisting of zinc (Zn), nickel (Ni) and aluminum (Al) layered double hydroxide coated carbon fibers (ZnNi/Al-LDHs/CFs) was prepared by electrochemical method with convenient recovery and separation. The structures, morphologies, and photo-electro catalytic properties of ZnNi/Al-LDHs/CFs were characterized by X-ray diffraction, infrared spectroscopy, field emission scanning electron microscopy, inductively coupled plasma atomic emission spectrometry and electrochemical impedance spectroscopy techniques. The excellent photo-electro bifunctional catalytic properties were obtained with the ZnNi/Al-LDHs/CFs composite as compared to that of Zn/Al-LDHs/CFs (photo catalyst) or Ni/Al-LDHs/CFs (electrocatalyst) alone, which could be used in the electro-catalytic oxidations of methanol and ethanol, as well as the photo-electro synergistically catalytic degradation of 2,6-dichlorophenol.
    Latest and Hot Papers
    Latest and Hot Papers
    ZHAN Dong-ping
    2018, 24(4):  401-402. 
    Asbtract ( 529 )   PDF (301KB) ( 501 )  
    Related Articles | Metrics
    Brief Account on the Editorial Board Conference of Journal of Electrochemistry
    Editorial Office of Journal of Electrochemistry
    2018, 24(4):  403-405. 
    Asbtract ( 512 )   PDF (342KB) ( 315 )  
    Related Articles | Metrics