物理化学学报 >> 2015, Vol. 31 >> Issue (7): 1215-1218.doi: 10.3866/PKU.WHXB201506102

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常压微等离子体阳极与离子溶液界面的电荷转移反应

任中华, 陆跃翔, 袁航, 王哲, 于波, 陈靖   

  1. 清华大学核能与新能源技术研究院, 北京100084;清华大学放射性废物处理北京市重点实验室, 北京100084
  • 收稿日期:2015-04-24 修回日期:2015-06-10 发布日期:2015-07-08
  • 通讯作者: 陆跃翔 E-mail:luyuexiang@mail.tsinghua.edu.cn
  • 基金资助:

    国家自然科学基金(21390413, 21405090, 91426302), 长江学者和创新团队发展计划(IRT13026), 清华大学自主科研计划(2014z22063)资助项目

Charge-Transfer Reactions at the Interface between Atmospheric- Pressure Microplasma Anode and Ionic Solution

REN Zhong-Hua, LU Yue-Xiang, YUAN Hang, WANG Zhe, YU Bo, CHEN Jing   

  1. Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, P. R. China;Beijing Key Laboratory of Radioactive Waste Treatment, Tsinghua University, Beijing 100084, P. R. China
  • Received:2015-04-24 Revised:2015-06-10 Published:2015-07-08
  • Contact: LU Yue-Xiang E-mail:luyuexiang@mail.tsinghua.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21390413, 21405090, 91426302), Program for Changjiang Scholars and Innovative Research Team in University, China (IRT13026), and Tsinghua University Initiative Scientific Research Program, China (2014z22063).

摘要:

常压微等离子体电极是一种有望取代常用贵金属电极用于电化学反应的气体电极. 然而目前关于微等离子体阳极与离子溶液界面反应的研究及其用于金属电沉积的报道还较少. 本文使用常压微等离子体作为阳极, 通过紫外-可见吸收光谱监测阳极电解液中亚铁氰化钾被氧化生成的铁氰化钾的含量, 发现铁氰化钾的含量随放电时间的延长而增加, 并且其增加的速率与放电电流成比例. 在放电结束后, 随着放置时间的延长铁氰化钾的含量继续升高, 其升高的速率与放电时间的长短有关. 放电结束后铁氰化钾含量的增加速率远小于放电时的增加速率. 实验结果表明微等离子体电极可以作为气体阳极在等离子体和液体界面进行电荷传输, 并引发电化学反应, 同时在放电的过程中产生了氧化活性物质. 在饱和硫酸铜溶液中, 使用微等离子体阳极可以在不锈钢阴极上进行铜的电沉积, 电流效率达到90%.

关键词: 微等离子体, 阳极, 电荷转移, 界面, 电沉积

Abstract:

Atmospheric- pressure microplasma is an attractive gaseous electrode, and may replace the commonly used rare metal electrodes for electrochemical reactions. The reactions at the plasma anode-liquid interface have not been well investigated, and application of plasma anodes to electrodeposition is still rare. In this communication, by choosing the oxidation of ferrocyanide to ferricyanide as a model reaction, we carefully investigated the charge-transfer reaction at the interface between a plasma anode and an ionic solution. The results showed that ferrocyanide was progressively oxidated to ferricyanide over time, and the rate of oxidation was proportional to the discharge current. We also found that after the discharge the oxidation percent of ferrocyanide still increased approximately linearly with storage time, and the increasing rate was dependent on the discharge time. The rate of oxidation after discharge was much lower than that caused by discharge. These results demonstrate that atmospheric-pressure microplasma could act as a gaseous anode for transferring positive charges at the plasma-liquid interface and inducing electrochemical reactions in solution. During discharge, oxidative active species were also produced. We also successfully electrodeposited copper on stainless steel with the assistance of a microplasma anode in CuSO4 saturated solution, and the current efficiency was about 90%.

Key words: Microplasma, Anode, Charge transfer, Interface, Electrodeposition

MSC2000: 

  • O646.9