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Full-Text Articles in Physical Sciences and Mathematics

Synthesis Of Porous Carbon Nanosheets And Its Application In Sodium-Ion Battery, Jing-Fei Zhang, Jing Lu, Xiao-Yu Yang, Yun-Di Huang, Lin Xu, Dong-Mei Sun, Ya-Wen Tang Dec 2015

Synthesis Of Porous Carbon Nanosheets And Its Application In Sodium-Ion Battery, Jing-Fei Zhang, Jing Lu, Xiao-Yu Yang, Yun-Di Huang, Lin Xu, Dong-Mei Sun, Ya-Wen Tang

Journal of Electrochemistry

Owning to sodium’s high abundance, relatively low cost, similar chemical properties to Li and very suitable redox potential of E0(Na+/Na) = -2.71 V versus SHE which is only 0.3 V above that of lithium, rechargeable sodium ion battery hold much promise as potential alternatives to current lithium ion batteries for energy storage applications. Carbon material is regarded as the most promising anode candidate for sodium ion battery. Particularly, carbon nanosheet with porous structure and high conductivity is expected to have improved sodium ion storage properties. In this paper, we present a two-step pyrolysis-based method for facile synthesis of porous carbon …


Intercalation Of Clo4- Into Hopg Investigated By Ec-Stm, Xiao-Yan Hu, Alice Aliwowe, Jia-Wei Yan, Bing-Wei Mao Dec 2015

Intercalation Of Clo4- Into Hopg Investigated By Ec-Stm, Xiao-Yan Hu, Alice Aliwowe, Jia-Wei Yan, Bing-Wei Mao

Journal of Electrochemistry

The electrochemical intercalation and surface morphology of highly oriented pyrolytic graphite (HOPG) electrode in 2 mol•L-1 HClO4 were studied by in situ scanning tunneling microscopy (STM) and cyclic voltammetry (CV). Based on the step-height changes observed before and after the intercalation, the effects of different step sites on intercalation are compared. The feasibility, reversibility and speed of intercalation are discussed. The intercalation of ClO4- into HOPG can be divided into three types depending on the number of graphite layers at the step site: When the layers of graphite are more than three, the intercalation becomes feasible; …


Electrochemical Properties Of Graphene/Porous Nano-Silicon Anode, Chun-Li Li, Guang Yang, Ping Zhang, Zhi-Yu Jiang Dec 2015

Electrochemical Properties Of Graphene/Porous Nano-Silicon Anode, Chun-Li Li, Guang Yang, Ping Zhang, Zhi-Yu Jiang

Journal of Electrochemistry

Porous nano-silicon (Si) was prepared by acid etching Al-Si alloy powder method, and used as an active material for fabricating a grapene/porous nano-Si electrode. The results of SEM and TEM measurements indicated that porous nano-Si powder was uniformly mixed with graphene by emulsification dispersion-ultrasonication method. As an anode for lithium ion battery, the graphene/porous nano-Si electrode presented relatively high performance in 1 mol•L-1 LiPF6/EC:DMC = 1:1(by volume) + 1.5% (by mass) VC solution. At the charge and discharge current densities of 0.5A•g-1, the first discharge capacity was 1768.6 mAh•g-1 with coulombic efficiency of 68.3%. The discharge …


Effect Of Carbon Nanotubes On Anodic Properties Of Ti/Ru-Ir-Sn Oxides, Feng Lian, Yong-Lei Xin, Bo-Jiang Ma, Li-Kun Xu Aug 2015

Effect Of Carbon Nanotubes On Anodic Properties Of Ti/Ru-Ir-Sn Oxides, Feng Lian, Yong-Lei Xin, Bo-Jiang Ma, Li-Kun Xu

Journal of Electrochemistry

The Ru-Ir-Sn metal oxide anodes coated on titanium (Ti/Ru-Ir-Sn) were prepared by thermal decomposition. The effects of amounts of carbon naotubes (CNTs) on anodic properties were studied by TGA, SEM, EDS, cyclic voltammetry, EIS, polarization measurements and accelerated life test. The thermogravimetric analysis and EDS spectrum data showed that the high temperature oxidation decomposition of CNTs did not take place under the condition of the sintering temperature of 470 ℃, and the CNTS still existed in the anode coating in an element form. Compared with the contrast samples, the surface crack of the coating increased, but remained typical morphology. Adding …


Effect Of Adsorption Potential On Co Oxidation At Au@Pt Nanoparticles Electrodes, A Surface Enhanced Raman Spectroscopic Study, Pu Zhang, Yi Wei, Yong-Li Zheng, Yan-Xia Chen, Zhong-Qun Tian Aug 2015

Effect Of Adsorption Potential On Co Oxidation At Au@Pt Nanoparticles Electrodes, A Surface Enhanced Raman Spectroscopic Study, Pu Zhang, Yi Wei, Yong-Li Zheng, Yan-Xia Chen, Zhong-Qun Tian

Journal of Electrochemistry

The adsorption/oxidation of CO on the 55 nm Au@0.7 nm Pt nanoparticles electrode in both potentiodynamic and potentiostatic modes were investigated by surface enhanced Raman spectroscopy in a thin layer electrochemical flow cell under controlled mass transport, with the aim of clarifying the origin CO oxidation at lower electrode potentials (in current pre-wave region of corresponding cyclic voltammograms). Our results demonstrated that the CO oxidation kinetics differed significantly from the three kinds of different CO adsorption history, with almost no CO oxidation current in the pre-peak potential region after 0.35 VRHE CO adsorption with or without subsequent holding the …


Broadband Sum-Frequency Generation Spectroscopic Invstigations Of Thiocyanate On Polycrystalline Au Electrode In Alkaline Solutions, Mei Xu, Jing-Jing Wang, Zhi-Chao Huangfu, Ng Ying Wa, Yu-Han He, Zhao-Hui Wang Aug 2015

Broadband Sum-Frequency Generation Spectroscopic Invstigations Of Thiocyanate On Polycrystalline Au Electrode In Alkaline Solutions, Mei Xu, Jing-Jing Wang, Zhi-Chao Huangfu, Ng Ying Wa, Yu-Han He, Zhao-Hui Wang

Journal of Electrochemistry

Broadband sum frequency generation (BB-SFG) spectroscopy has been used to investigating the potential-dependent adsorption behaviors of thiocyanate ions on polycrystalline Au electrode in alkaline solutions. During the positive scan, a change in the Stark slope (dωC-N/dE) for C—N stretching mode can be observed in the range of -1.1 V ~ 0.2 V (vs. SCE), which implies that the orientation of adsorbed thiocyanate ions at Au electrode surface changes from N-bound (dωC-N/dE=45 cm-1·V-1) form to S-bound (dωC-N/dE = 16.2 cm-1·V-1 …


Preparation And Characterization Of Carbon Supported Pd-Sb Composite Nanocatalysts For Formic Acid Electrooxidation, Long-Long Wang, Xiao-Lu Cao, Ya-Jun Wang, Jin-Hao Ping, Qiao-Xia Li Aug 2015

Preparation And Characterization Of Carbon Supported Pd-Sb Composite Nanocatalysts For Formic Acid Electrooxidation, Long-Long Wang, Xiao-Lu Cao, Ya-Jun Wang, Jin-Hao Ping, Qiao-Xia Li

Journal of Electrochemistry

Palladium is considered as an efficient anode catalyst with high catalytic activity for electrooxidation of formic acid. To further improve the catalytic activity and stability, alloying or surface modification with Sb is an effective way. In this work, the well dispersed carbon supported Pd-Sb composite nanocatalysts (Pd-Sb/C) were synthesized by traditional impregnation reduction method with trisodium citrate as the complexing agent, sodium borohydride as the reducing agent. The morphologies of Pd-Sb/C and the effects of molar ratio of Pd to Sb on the electrocatalytic properties of Pd-Sb/C for HCOOH electrooxidation were studied. The XRD and XPS analyses on the as-prepared …


Porous Co3O4 Hollow Nanospheres Cathode Catalyst For High-Capacity And Long-Cycle Li-Air Batteries, Tong Liu, Na Li, Qing-Chao Liu, Xin-Bo Zhang Apr 2015

Porous Co3O4 Hollow Nanospheres Cathode Catalyst For High-Capacity And Long-Cycle Li-Air Batteries, Tong Liu, Na Li, Qing-Chao Liu, Xin-Bo Zhang

Journal of Electrochemistry

In this paper, a high specific surface area of porous Co3O4 hollow nanospheres was successfully synthesized via hydrothermal carbonization at 140 oC, followed by calcination using cobalt nitrate hexahydrate (Co(NO3)2·6H2O), hexamethylenetetramine (HMT), sucrose, and sodium citrate (Na3C6H5O7). The porous Co3O4 hollow nanospheres consisted of nanoparticles with high specific surface area of mesoporous structure, and could provide active reaction sites for OER and ORR. When used as lithium-air battery cathode catalyst, the Co3O4/Super P (SP) electrode …


Sensitive Detection Of Hydroxyl Radical Based On Silver-Enhanced Gold Nanoparticle Label, Yan Yang, Peng Yu, Xiao-Hua Zhang, Jin-Hua Chen Feb 2015

Sensitive Detection Of Hydroxyl Radical Based On Silver-Enhanced Gold Nanoparticle Label, Yan Yang, Peng Yu, Xiao-Hua Zhang, Jin-Hua Chen

Journal of Electrochemistry

A novel DNA-based electrochemical sensor has been successfully constructed for sensitive detection of hydroxyl radical (·OH) based on the silver-enhanced gold nanoparticle label. Thiolated DNA1 was firstly immobilized on the gold electrode through Au—S bonds. The ·OH generated from Fenton reaction could induce serious oxidative damage of the DNA1 layer on the electrode surface. Then DNA2-functionalized gold nanoparticles (DNA2-AuNPs) were linked on the electrode through the hybridization between DNA2 and undamaged DNA1. Based on the catalytic reduction of silver ion by AuNPs, a silver layer was formed on the surface of AuNPs. The quantitative assay of ·OH was carried out …


A Novel Nitrite Sensing Electrode Based On Au/Fe3O4/Chitosan Nanocomposite, Ying Dong, Yong Wang, Huan-Huan Xing, Jian-Ying Qu Feb 2015

A Novel Nitrite Sensing Electrode Based On Au/Fe3O4/Chitosan Nanocomposite, Ying Dong, Yong Wang, Huan-Huan Xing, Jian-Ying Qu

Journal of Electrochemistry

A novel nitrite sensing electrode based on gold nanoparticles and iron oxides (Fe3O4) magnetic nanoparticles was fabricated with chitosan as the protective film on glassy carbon matrix. Experiment results showed that the sensing electrode exhibited good electrocatalytic activity toward oxidation of nitrite, and the oxidation peak current increased linearly with the concentration of nitrite varying from 5.0×10-6 to 2.0×10-3 mol·L-1 (R=0.9996) with a detection limit of 7.1×10-7 mol·L-1 (S/N=3). The sensing electrode exhibited good sensitivity, selectivity and repeatability.


Nanosized Fe2O3 On Three Dimensional Hierarchical Porous Graphene-Like Matrices As High-Performance Anode Material For Lithium Ion Batteries, Qin-Wei Zhang, Yun-Yong Li, Pei-Kang Shen Feb 2015

Nanosized Fe2O3 On Three Dimensional Hierarchical Porous Graphene-Like Matrices As High-Performance Anode Material For Lithium Ion Batteries, Qin-Wei Zhang, Yun-Yong Li, Pei-Kang Shen

Journal of Electrochemistry

Ferric oxide (Fe2O3) as a promising anode material for lithium ion battery is due to its high theoretical capacity (1007 mAh·g-1), earth abundance and low cost. The nanosized Fe2O3 on the three dimensional hierarchical porous graphene-like network (denoted as Fe2O3-3D HPG) has been synthesized by homogeneous precipitation and heat treatment. The 3D HPG can provide a highly conductive structure in conjunction to support well contacted Fe2O3 nanoparticles, and effectively enhance the mechanical strength of the matrices during volume changes, as well as improve the …


Effects Of Etchants On Surface Morphologies And Electrochemical Performance Of Iro2-Mno2 Anodic Nano-Coatings, Qing-Guo Fan, Zhi-Guo Ye, Hui-Min Meng, Chun-Min Lu Feb 2015

Effects Of Etchants On Surface Morphologies And Electrochemical Performance Of Iro2-Mno2 Anodic Nano-Coatings, Qing-Guo Fan, Zhi-Guo Ye, Hui-Min Meng, Chun-Min Lu

Journal of Electrochemistry

The IrO2-MnO2 anodic nano-coatings were prepared by the traditional thermal decomposition method on the different surfaces of Ti substrates pretreated by different etchants (HCl, H2SO4, C2H2O4 and HF). Surface morphologies and electrochemical performance of the Ti based IrO2-MnO2 anodic coatings were investigated by field emission scanning electron microscopy (FESEM), cyclic voltammetry (CV) and polarization techniques. Analysis showed that the denser IrO2 nano-particles with longer dimensions were obtained at the IrO2-MnO2 anodic coating surfaces on the Ti substrates etched by HF and …