溶剂及电解质盐对氧在有机电解液体系中电化学还原的影响  

Effects of Solvents and Electrolyte Salts on the Electrochemical Reduction of Oxygen in Non-aqueous Electrolytes

作　　者：田艳艳[1] 武巍[1] 高军[1] 杨勇[1] 

机构地区：[1]厦门大学固体表面物理化学国家重点实验室,化学化工学院化学系,福建厦门361005

出　　处：《电化学》2010年第4期420-424,共5页Journal of Electrochemistry

基　　金：国家973计划课题(2007CB209702);总装科技项目(61310602-3)资助

摘　　要：应用线性循环伏安(CV)法研究了氧在几种有机电解液体系中的电化学还原过程.实验表明,氧在四丁基六氟磷酸铵(TBAPF6)/乙腈(MeCN)或TBAPF6/丙烯碳酸酯(PC)电解液中,均首先发生1电子还原生成O2-的过程,但电位回扫还原过程的可逆性却表现出很大差异:在乙腈溶液中反应可逆性较好,CV曲线表现出一对可逆的氧化还原峰,而在丙烯碳酸酯为溶剂的电解液中,氧还原过程可逆性差,不仅初始氧还原电流显著减小,而且表征O2-氧化的电流峰几乎消失.此外,电解质盐对氧还原过程也具有很大影响,在六氟磷酸锂(LiPF6)/乙腈电解液中,氧的还原可逆性较差.The electrochemical reduction processes of oxygen in different non-aqueous solvents such as acetonitrile（MeCN）,propylene carbonate（PC） and their mixtures were investigated by cyclic voltammetry method.The results indicated a one electron reduction of oxygen to O2-occured in these systems as a first step reduction,no matter whether in tetrabutylammonium hexafluorophosphate（TBAPF6）/MeCN or TBAPF6/PC electrolyte.However,the CV curves in 0.1 mol·L-1 TBAPF6/MeCN showed a couple of reversible redox peaks,indicating that the reduction process of oxygen was irreversible in the 0.1 mol·L-1 TBAPF6/PC electrolyte.In the PC-based electrolyte,the reduction current peak reduced largely and the oxidation peak of O2-almost disappeared as compared to that of the former electrolytes.The possible interaction mechanism between O2-and propylene carbonate is proposed.In addition,the kind of salts in solution has great effect on the reduction process of oxygen.

关 键 词：有机电解液体系 锂氧电池 氧还原 1电子还原 

分 类 号：O646.54[理学—物理化学]