掺杂LaNiO_3型双功能氧电极的电化学性能  

Electrochemical Properties of Doped LaNiO_3 Perovskite Oxide Bi-Functional Oxygen Electrodes

作　　者：宋世栋[1] 唐致远[1] 潘丽珠[1] 南俊民[2] 

机构地区：[1]天津大学化工学院,天津300072 [2]华南师范大学化学系,广州510631

出　　处：《天津大学学报》2006年第1期39-44,共6页Journal of Tianjin University(Science and Technology)

基　　金：教育部博士后重点基金资助项目(20273047).

摘　　要：双功能氧电极的开发是二次空气电池的关键问题,以开发高性能的双功能氧电极为目的,制备了 LaNi1-yMyO3(M=Co,Fe;y=0,0．2)钙钛矿氧化物作为双功能氧电极的电催化剂,以活性碳为载体,聚四氟乙烯乳液为粘接剂制备双功能氧电极．采用三电极体系测试了氧电极的稳态极化曲线和电化学交流阻抗谱,并对其阴极极化和阳极极化的交流阻抗谱图进行分析．通过等效电路的拟合研究了该系列双功能氧电极氧还原反应的工作机理．结果表明,对于LaNiO3化合物,B位掺杂可显著提高催化剂的电催化性能,电极氧还原反应的极化主要由电荷转移反应和Nernstian扩散过程造成．The development of bi-functional oxygen electrode is the key problem of secondary air batteries. For developing the bi-functional oxygen electrode with high catalytic properties, LaNi1 -yMyO3 （M = Co, Fe ;y = 0, 0.2） perovskite oxides were used as hi-functional oxygen electrodes electro-catalysts. The activities of polytetrafluoroethylene（PTFE） bonded bi-functional oxygen electrodes made by the perovskite-type catalyst dispersed on active carbon were investigated using steady polarization curves, cyclic voltampere curves and electrochemical impedance spectroscopy methods. The impedance spectra of both cathodic and anodic polarization were analyzed. The electrochemical parameters of the oxygen reduction reaction were obtained by fitting the experimental impedance data to an equivalent circuit containing two Nemstian diffusion terms. The results showed that the oxygen reduction activity were improved by doping Fe^3＋ and Co^3＋ ions on B site of LaNiO3 oxides. The polarization resistance was mainly caused by the slow Nernstian diffusion and charge transfer reaction.

关 键 词：双功能氧电极 金属氢化物-空气电池 钙钛矿复合氧化物 电化学阻抗谱 可再生燃料电池 

分 类 号：O606[理学—化学]