Ca掺杂LNF阴极材料的制备与电化学性能改善  

Preparation and Electrochemical Performance Improvement of Alkaline Earth Metal Ca Doped LNF Cathode

作　　者：谢满意 蔡长焜 安胜利[1,2] 郜建全 薛柯[1,2] 彭继华 Xie Manyi;Cai Changkun;An Shengli;Gao Jianquan;Xue Ke;Peng Jihua(School of Materials and Metallurgy,Inner Mongolia University of Science and Technology,Baotou 014010,China;Inner Mongolia Key Laboratory of Advanced Ceramic Materials and Devices,Baotou 014010,China)

机构地区：[1]内蒙古科技大学材料与冶金学院,内蒙古包头014010 [2]内蒙古自治区先进陶瓷材料与器件重点实验室,内蒙古包头014010

出　　处：《稀有金属材料与工程》2020年第9期3099-3106,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51974167)。

摘　　要：近年来,LaNi0.6Fe0.403-δ阴极材料因在金属连接体下具有优异的抗铬毒化性能备受关注,但其电化学性能相对较低。通过Ca^2+掺杂LaNi0.6Fe0.4O3-δ(LNF)阴极材料改善电化学性能,实验采用甘氨酸燃烧法制备La1-xCaxNi0.6Fe0.4O3-δ(LCNF)阴极材料,Ca2+掺杂量x=0.05,0.10,0.15,0.20。利用XRD衍射表征材料的物相组成,SEM观察阴极材料的微观结构,XPS分析阴极材料表面元素的化学形态,电化学交流阻抗谱技术分析阴极材料的电化学活性。结果表明,LCNF阴极材料随着Ca^2+掺杂量的增加,氧还原反应活化能减小,这一现象与DRT(弛豫时间分布)分析结果相吻合。LCNF(x=0.20)阴极材料在750℃具有最小的极化阻抗(0.88Ω·cm^2),与LNF阴极材料相比表现出更加优异的氧催化活性,使LCNF阴极材料在IT-SOFC具有更加广阔的应用前景。In recent years,LaNi0.6Fe0.4O3-δcathode materials have been paid much attention to due to their chromium poisoning resistance under metal interconnects,but they have relatively low electrochemical performance.This paper aims to improve the electrochemical performance of LNF cathode by Ca doping.La1-xCaxNi0.6Fe0.4O3-δ(x=O,0.05,0.10,0.15,0.20,LCNF)cathode material was prepared by a glycine combustion method.The phase composition of the material was characterized by X-ray diffraction.The micro structure of the cathode material was observed by SEM.The chemical forms of elements on the surface of cathode materials were analyzed by XPS.The electrochemical activity of the cathode material was analyzed by an AC impedance spectroscopy.The results show that the activation energy of oxygen reduction reaction decreases with the increase of Ca^2+doping content in La1-xCaxNi0.6Fe0.403-δcathode material,which is consistent with the DRT(distribution of relaxation times)analysis.The La0.08Ca0.2Ni0.6Fe0.4O3-δcathode material has the lowest polarization resistance(0.88Ω·cm2)at 750~,and exhibits better oxygen catalytic activity than the undoped LNF material,making the LCNF cathode have a broader application prospect in IT-SOFC.

关 键 词：钙钛矿型阴极材料 LaNi0.6Fe0.4O3-δ 掺杂 极化电阻 弛豫时间分布 

分 类 号：TM911.4[电气工程—电力电子与电力传动]