Hydrothermal Synthesis Of Pure Li4Ti5O12 And Its Electrochemical Performance,
2013
Institute of Electrochemical and Energy Technology, Department of Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
Hydrothermal Synthesis Of Pure Li4Ti5O12 And Its Electrochemical Performance, Wen-Jun Xie, Yu-Shi He, Hong Wang, Xiao-Zhen Liao, Zi-Feng Ma
Journal of Electrochemistry
Spinel Li4Ti5O12 was prepared by hydrothermal method using commercial anatase (TiO2) and lithium hydroxide (LiOH) as raw materials. The effects of the LiOH concentration of lithium hydroxide, hydrothermal reaction time and calcination temperature on the structure and electrochemical performance of Li4Ti5O12 were investigated. The formation process of Li4Ti5O12 was also proposed. The micro-structure and morphology wereas characterized by XRD, SEM, TEM techniques, and the electrochemical performance was analyzed by galvanostatic charge-discharge test. The results show that the pure phase spinel Li4Ti …
Preparation And Catalytic Properties Of Feco Alloy Nanocatalyst,
2013
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Preparation And Catalytic Properties Of Feco Alloy Nanocatalyst, Ming-Xuan Li, Jie-Lian Ou, Sheng-Pei Chen, Peng Wang, Bin-Bin Xu, Shi-Gang Sun
Journal of Electrochemistry
The FeCo alloy nanoparticles were electrodeposited on glassy carbon electrode by chronoamperometry and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the shapes of FeCo nanoparticles were cubes with an average size of 65 nm. The atom ratio of Fe and Co is 1:1. As indicated from the pattern of selected area electron diffraction (SAED), the FeCo cubic nanoparticles were single crystal which belonged to body-centered cubic with an interval of 0.201 nm referring to the (110) facets of FeCo alloy. The FeCo cubic nanoparticles exhibited the enhanced electrocatalytic …
Electrochemical Synthesis Of Hierarchical Dendritic Polyaniline Nanostructures,
2013
Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350004, China
Electrochemical Synthesis Of Hierarchical Dendritic Polyaniline Nanostructures, Shao-Huang Weng, Jian-Zhang Zhou, Zhong-Hua Lin, Xin-Hua Lin
Journal of Electrochemistry
In this work, the p-TSA doped and hierarchical dendritic nanostructured polyanilines (PANI) have been prepared by potentiostatic electropolymerization without using any templates at room temperature. The mechanism of the polymerization has been discussed according to the electrodeposition curves. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to confirm the formation of uniform hierarchical dendritic structure on PANI. UV-Vis spectroscopy (UV-Vis) and infrared spectroscopy (FTIR) proved that the prepared PANI is in the form of emeraldine salt. The templateless electrodeposition method is simple, easy to operate, can be applied to fabricate other nanostructures of conducting polymers.
Electrochemical Performance Of Lifepo4/C Synthesized Via Aqueous Solution-Evaporation Route,
2013
Department of Chemistry, Nanchang University, Nanchang 330031, Jiangxi, China;
Electrochemical Performance Of Lifepo4/C Synthesized Via Aqueous Solution-Evaporation Route, Ning-Yu Gu, Xing-Hua He, Yang Li
Journal of Electrochemistry
The LiFePO4/C samples have been synthesized via an aqueous solution-evaporation route with LiH2PO4, FeC2O4.2H2O as raw materials and citric acid as a carbon source. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to analyze structure and morphology of the samples. The electrochemical performances of the LiFePO4/C cathodes were characterized by charge/discharge cures and electrochemical impedance spectroscopy (EIS). The results show that the LiFePO4/C sample, calcined at 700 °C and contained 3.03% (by mass) carbon, exhibited a highly pure …
Preparation And Methanol Electrooxidation Of Pt/Pmo12/Pedot/Gc Electrodes,
2013
Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin 541004, Guangxi, China;
Preparation And Methanol Electrooxidation Of Pt/Pmo12/Pedot/Gc Electrodes, Jing-Hua Ma, Rui-Xiang Wang, Yi-Liang Tan, Shan-Shan Wang, Yan-Qin Zhang, You-Jun Fan
Journal of Electrochemistry
Modification of phosphomolybdic acid (PMo12) on poly(3,4-ethylenedioxythiophene) (PEDOT) film (PEDOT/GC) obtained through the electrochemical polymerization was performed using adsorption method (PMo12/PEDOT/GC), followed by electrodepositing Pt on PMo12/PEDOT/GC to prepare Pt/PMo12/PEDOT/GC electrode. Effects of PMo12 and PEDOT on the methanol oxidation performance of electrode were investigated. Results showed that PMo12 obviously changed the morphology and structure of Pt loaded on the electrode, leading to the formation of sharp thorns at the edge of Pt nanostructures. Cyclic voltammetry and chronoamperometry data demonstrated that the catalytic activities of methanol electrooxidation on the Pt/PMo …
Synthesis And Electrochemical Performance Of Si/C Composite Modified By Pani,
2013
State Key Laboratory for Surface Physics & Chemistry, China Academy of Engineering Physics, Mianyang 621907, Sichuan, China;
Synthesis And Electrochemical Performance Of Si/C Composite Modified By Pani, Guang-Hui Zhang, Pei-Kang Shen, Ge Sang, Ren-Jin Xiong
Journal of Electrochemistry
Silicon/carbon (Si/C) composite materials were prepared through high-energy ball milling and high-temperature solid-phase method, and then coated with thin polyaniline (PAni) film by oxidation. The microstructure and component of the composites were characterized by SEM, XRD, IR, TG, and the electrochemical performance was investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge tests. The results showed that the surface of PAni/Si/G/C composite was coating with complete lamellar structure of PAni film. Its reversible capacity was 784 mAh·g-1 and 690 mAh·g-1 could be maintained after 50th charge-discharge cycles.
Synthesis Of Lifepo4/C Cathode By Sol-Gel And Calcining Method With Chitosan Monomer,
2013
College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China;
Synthesis Of Lifepo4/C Cathode By Sol-Gel And Calcining Method With Chitosan Monomer, Jia Xu, Yan-Yan Wang, Rui Wang, Bo Wang, Yue Pan, Dian-Xue Cao, Gui-Ling Wang
Journal of Electrochemistry
The LiFePO4/C cathode materials for Li-ion battery were synthesized by sol-gel and calcining method using chitosan monomer as a carbon source and a gelating agent. The structures and morphologies were characterized by X-ray diffraction spectroscopy (XRD) and scanning electron microscopy (SEM). The electrochemical performance was investigated by the galvanostatic charge–discharge test. When the molar ratios between chitosan monomer and LiFePO4 were 1:1.2, the LiFePO4/C cathode calcined at 600 oC showed the best performance. The particle sizes ranged 200 ～ 400 nm. The initial discharge capacity of 155 mAh·g-1 was achieved at room temperature …
Synthesis And Electrocatalysis Of Pdcu Alloy Nanocrystals,
2013
State Key Laboratory of Eleetroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
Synthesis And Electrocatalysis Of Pdcu Alloy Nanocrystals, Hai-Bin Wu, Rui-Zhong Zhang, Wei Chen
Journal of Electrochemistry
Monodispersed PdCu alloy nanoparticles were synthesized by co-reduction of Cu(acac)2 and Pd(acac)2 with 1, 2-hexadecanediol. The spherical and popcorn-like shapes of PdCu alloy nanoparticles were obtained by changing the ratios of mixed surface protecting ligands of 1-octadecene, and oleylamine or oleic acid. TEM and XRD measurements showed that both PdCu nanoparticles are alloy nanocrystals dominated with (111) planes and the average sizes are 12.7 ± 0.18 and 20.4 ± 0.31 nm for he spherical and popcorn-like PdCu nanoparticles, respectively. The electrocatalytic activities of the PdCu nanocrystals for formic acid oxidation were evaluated by electrochemical cyclic voltammetry (CV). The result showed …
Properties Of Carbon Coated Tin Negative Electrode For Lithium-Ion Battery,
2013
School of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China
Properties Of Carbon Coated Tin Negative Electrode For Lithium-Ion Battery, Gui-Chang Liu, Xiao-Xiao Shen, Li-Da Wang
Journal of Electrochemistry
Carbon coated tin power was prepared by decomposing glucose applying a hydrothermal method, and was further used as the active material for negative electrode of lithium secondary battery. Charge-discharge tests show that the carbon coated tin electrode with the addition of 5 wt.% acetylene black as a conductive agent could obtain an initial discharge capacity of 967 mAh·g-1 and a discharge capacity of 362 mAh·g-1 after 50 cycles, which is much higher than that of tin electrode (166 mAh·g-1 after 50 cycles). The coated carbon hinders the agglomeration of tin powder, reduces the irreversible capacity loss of …
Solar Cell Design Using Metamaterials,
2013
University of Nevada, Las Vegas
Solar Cell Design Using Metamaterials, Yang Liu, Yitung Chen, Jichun Li
College of Engineering: Graduate Celebration Programs
Natural structure with simultaneous negative permittivity and permeability has not been discovered yet. However, using specially-designed metal embedded in dielectric bodies can achieve a kind of artificial negative index. This periodic structure which is smaller than the guided wavelength is known as a metamaterial. However, recent designs of metamaterials have some disadvantages when they are used in the application of solar cell. The perfect absorption is only within a narrow band, and for most of the solar spectrum, the absorption is no more than 10%. Here, a new kind of absorber for the solar spectrum has been designed and analyzed, …
A Computation Model For Nanoantenna-Based Solar Cell With High Conversion Efficiency,
2013
University of Nevada, Las Vegas
A Computation Model For Nanoantenna-Based Solar Cell With High Conversion Efficiency, Yiyan Li, Ke-Xun Sun, Yingtao Jiang
College of Engineering: Graduate Celebration Programs
- Build a model of spiral nanoantenna and an antenna
array based solar cell collector. - Using Rao-Wilton-Glisson (RWG) basis functions to
simulate the spiral nanoantennas. - We calculate the frequency response of the radiation
gain as the indicator of receiving bandwidth which is a
key factor in conversion efficiency.
Impact Of Primary User Activity On The Performance Of Energy-Based Spectrum Sensing In Cognitive Radio Systems,
2013
Old Dominion University
Impact Of Primary User Activity On The Performance Of Energy-Based Spectrum Sensing In Cognitive Radio Systems, Sara L. Macdonald
Electrical & Computer Engineering Theses & Dissertations
Increasing numbers of wireless devices and mobile data requirements have led to a spectrum shortage. However spectrum utilization percentages are often low due to the current static spectrum allocation process where primary users (PUs) are given exclusive use to spectrum. Several mechanisms to increase spectrum utilization have been proposed including opportunistic spectrum access (OSA). Cognitive Radio (CR) is an emerging concept in wireless communication systems that aims to enable OSA in licensed frequencies by secondary users (SUs). CR systems are expected to sense the spectrum in order to determine if the PU is transmitting. Therefore OSA performance relies on the …
Microgrid Power Quality Analysis,
2013
California Polytechnic State University – San Luis Obispo
Microgrid Power Quality Analysis, Nikolai Kempcatala, Daniel Pleau, Scott Clemons
Electrical Engineering
The microgrid power quality analysis senior project addresses power quality assessment. Our senior project uses the PowerSight 3000 power measurement tool to record and analyze various electrical measurements including voltage, current, power, power factor, harmonics and AC frequency.
Our project will analyze power quality issues that result from switching from the utility grid to a smart grid run on primarily photovoltaic distributed generation. In the event of a utility failure, the smart grid can serve as an isolated grid for the system, this is called islanded mode. Our project assesses the reliability of operation in islanded mode. Our analysis should …
Dc House Distribution Panel,
2013
California Polytechnic State University - San Luis Obispo
Dc House Distribution Panel, Khanh Ho
Electrical Engineering
This paper details the process in designing the distribution panel, or circuit breaker box for a DC house. The main purpose of the project is to design a distribution panel that will provide electrical power to the DC house while also providing an electrical system protection through the use of circuit breakers, or fuses. An actual hardware design for the distribution panel was built and tested. The results demonstrate the functionality of the breaker box to supply power to the DC House ensuring safe operation of the DC House.
Electrochemical Performance Of Fe3O4/C Composites As Negative Material For Lithium-Ion Batteries,
2013
State Key Laboratory of optoeleetronic Materials and Technologies, Guangdong Province Key Laboratory of Lou-carbon Chemistry & Energy Conservation, School of Physics and Engineering, Sun Yat-sen University,Guangzhou 510275, China
Electrochemical Performance Of Fe3O4/C Composites As Negative Material For Lithium-Ion Batteries, Jun-Jie Cai, Shu Yao, Ze-Sheng Li, Hui Meng, Pei-Kang Shen
Journal of Electrochemistry
The Fe3O4/Carbon composites have been synthesized through coprecipitation pathway and by insitu aniline polymerization as a carbon source. Structural characterization and morphological study of the composites were investigated by using XRD, SEM and TEM techniques. The results showed that the nanosized Fe3O4 particles (40 ~ 80 nm) were encapsulated in the amorphous carbon. During the electrochemical tests, the Fe3O4/C composites exhibited high capaticity and excellent cycle ability, the retention of capaticity was about 1000 mAh·g-1 after 30 cycles of charge/discharge tests at 50 mA·g-1.
An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2C/Gc Catalyst,
2013
State Key Laboratory of Optoelectronic Materials and Technologies, Key Laboratory ofLow-carbon Chemistry&: Energy Conservation of Guangdong Province, Sehool of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275, China
An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2C/Gc Catalyst, Hai-Ping Huang, Xi-Yu Yao, Pei-Kang Shen
Journal of Electrochemistry
A 40% Pt on Mo2C/GC catalyst has been prepared by ion exchange method. The mechanism of methanol electrooxidation on Pt-Mo2C/GC and commercial Pt/C catalysts in acidic media was studied by cyclic voltammetry, XRD measurements and in-situ Fourier transform infrared spectroelectrochemistry. The results revealed that the Pt nanoparticles were uniformly dispersed on Mo2C/GC with an average particle size of 3 nm. The cyclic voltammetric and chronopotentiometric experiments indicated that Pt-Mo2C/GC catalyst exhibited a better performance for methanol oxidation than that of Pt/C in acid solution. A negative shift over 90 mV of the …
Oxygen Reduction Reaction On Glycin Modified Pt(111) Electrode,
2013
Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China;
Oxygen Reduction Reaction On Glycin Modified Pt(111) Electrode, Ming-Fang Li, Jing Kang, Ling-Wen Liao, Yan-Xia Chen, Shen Ye
Journal of Electrochemistry
O
xygen reduction reaction (ORR) on glycin (NH2CH2COOH) modified Pt(111) electrode has been investigated using hanging meniscus rotating disk electrode system (HMRD) in 0.05 mol•L-1 H2SO4 and 0.1 mol•L-1 HClO4 solutions, respectively. Cyclic voltammograms of the glycin modified Pt (111) electrode measured in 0.05 mol•L-1 H2SO4 solution similar to that of CN- modified Pt(111) electrodes, demonstrating that sulfate adsorption is strongly inhibited at the glycin modified Pt(111). From the polarization curve of ORR recorded in 0.05 mol•L-1 H2SO4 solution, it is …
Effect Of Ti/Pbo2 Electrodes Doped With Different Elements On Electrocatalytic Oxidation Characteristics Of Phenol,
2013
College of Chemistry, Jilin University, Changchun 130012, Jilin, China;
Effect Of Ti/Pbo2 Electrodes Doped With Different Elements On Electrocatalytic Oxidation Characteristics Of Phenol, Xiao-Lei Liu, Yuan-Yuan Dan, Hai-Yan Lu, Hai-Bo Lin, Ming-Li Ouyang, Chuan-Jun Yun
Journal of Electrochemistry
Three types of electrodes, namely, Ti/PbO2, F-doped PbO2 (Ti/PbO2-F) and nano-Co3O4-doped PbO2 (Ti/PbO2+Nano-Co3O4) electrodes, were prepared by electro-deposition method on the Ti substrate with the interlayer of SnO2-Sb2O5. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to study the compositions, structures and film morphologies of the electrodes. Electrocatalytic oxidation characteristics to phenol on the prepared electrodes were investigated by electrochemical method. The experimental results showed that compared with the Ti/PbO2 electrode, the potentials of oxygen …
A Dft Calculation Screening Of Pt-Based Bimetallic Catalysts For Oxygen Reduction,
2013
College of Chemistry and Chemical Engineering, Hunan University of Arts and Science, Changde 415000, Hunan, China
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 …
Sodium Carbonate Catalyzed Photoelectrochemical Water Splitting Over Tio2 Nanotubes Photoanode,
2013
Department of Chemistry, Qufu Normal University, Qufu 273165, Shandong, China;
Sodium Carbonate Catalyzed Photoelectrochemical Water Splitting Over Tio2 Nanotubes Photoanode, De-Sheng Kong, Jing Wang, Xue-Di Zhang, Xi Zhao, Chao Wang, Yuan-Yuan Feng, Wen-Juan Li
Journal of Electrochemistry
Surface recombination of the photogenerated electron-hole pairs at semiconductor/electrolyte interface is one of the most essential reasons responsible for lowering photoconversion efficiency (Φ) of light to chemical energy for photoelectrochemical (PEC) water splitting reaction. In this paper, the catalytic effect of sodium carbonate on the oxygen evolution reaction (OER) over TiO2 nanotubes photoanode during PEC water splitting was investigated by performing photocurrent and ac impedance measurements. It was demonstrated that the addiction of 1 mmol•L-1 Na2CO3 in 0.5 mol•L-1 NaClO4 electrolyte can effectively improve the charge transfer properties for the photogenerated holes across …
