固态氧化物阴极过程的离子扩散模型及其Ta2O5熔盐电解验证

doi:10.13208/j.electrochem.130886

电化学（中英文） ›› 2014, Vol. 20 ›› Issue (3): 266-271. doi: 10.13208/j.electrochem.130886

• 基础电化学近期研究专辑(武汉大学陈胜利教授主编) • 上一篇下一篇

固态氧化物阴极过程的离子扩散模型及其Ta₂O₅熔盐电解验证

陈华林¹，王志勇¹，金先波^1*，陈政^1,2

1. 武汉大学化学与分子科学学院，湖北武汉 430072；2. 诺丁汉大学工学院化学与环境工程系，诺丁汉NG7 2RD，英国

收稿日期:2013-09-02 修回日期:2013-11-06 出版日期:2014-06-28 发布日期:2013-11-11
通讯作者: 金先波 E-mail:xbjin@whu.edu.cn
基金资助:
国家自然科学基金项目（No. 21173161）及教育部新世纪人才计划项目（No. NCET-11-0397）资助

The Ionic Diffusion Model for the Solid Oxide Cathode and Its Verification by the Electrolysis of Ta₂O₅ in Molten CaCl₂

CHEN Hua-lin¹, WANG Zhi-yong¹, JIN Xian-bo^1*, Chen George Z.^1,2

1. College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China; 2. Department of Chemical and Environmental Engineering, and Energy and Sustainability Research Division, Faculty of Engineering, University of Nottingham, Nottingham NG7 2RD, UK

Received:2013-09-02 Revised:2013-11-06 Published:2014-06-28 Online:2013-11-11
Contact: JIN Xian-bo E-mail:xbjin@whu.edu.cn

摘要/Abstract

摘要： 固态氧化物阴极在氯化钙熔盐电解质中的脱氧速率可依据氧离子的稳态扩散模型（PRS模型）由固态氧化物阴极孔隙率P，还原后金属与还原前氧化物之间的摩尔体积比R，还原后阴极的体积收缩率S等参数直接计算. PRS模型重要意义还在于可提供极简单的公式以预测不同金属氧化物还原时固态阴极的优化孔隙率，而固态阴极孔隙率对其脱氧速率有显著影响. 对于Ta₂O₅电解，其固态阴极孔隙率不易大于50%. 相关理论预测结果得到了固态Ta₂O₅在氯化钙熔盐中电解实验的良好验证，表明PRS模型对固态化合物阴极的快速、高效电解具有重要的指导意义.

关键词: 固态氧化物, 熔盐电解, 扩散模型, Ta₂O₅, 钽粉

Abstract: The deoxidation speed of a solid oxide cathode in molten CaCl₂ can be estimated by the PRS steady diffusion model of O^2-, which correlates the deoxidation speed with the precursor porosity, P, the metal-to-oxide molar volume ratio, R, and the cathode volume shrinkage S. The PRS model indicates that the porosity of the oxide cathode has important influence on the deoxidation speed, and provides a very simple equation for the prediction of the optimal cathode porosity. For the electrolysis of Ta₂O₅, the porosity of the cathode is better to be within 50%. The model and its predictions has been well verified by the electrolysis of solid Ta₂O₅ in molten CaCl₂, suggesting the great significance of the PRS model for the high speed and high current efficiency electrolysis of solid compound cathode in molten salts.

中图分类号:

O646.5

陈华林，王志勇，金先波*，陈政. 固态氧化物阴极过程的离子扩散模型及其Ta₂O₅熔盐电解验证[J]. 电化学（中英文）, 2014, 20(3): 266-271.

CHEN Hua-lin, WANG Zhi-yong, JIN Xian-bo*, Chen George Z.. The Ionic Diffusion Model for the Solid Oxide Cathode and Its Verification by the Electrolysis of Ta₂O₅ in Molten CaCl₂[J]. Journal of Electrochemistry, 2014, 20(3): 266-271.

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固态氧化物阴极过程的离子扩散模型及其Ta₂O₅熔盐电解验证

The Ionic Diffusion Model for the Solid Oxide Cathode and Its Verification by the Electrolysis of Ta₂O₅ in Molten CaCl₂

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