二次烧结气氛对La0.7Sr0.3MnO3氧还原催化活性的影响  

Effect of Secondary Sintering Atmosphere on the Catalytic Activity of La_(0.7)Sr_(0.3)MnO_3 for Oxygen Reduction

作　　者：汪广进[1,2] 程凡[1] 徐甜[2] 余意[2] 文胜[1] 龚春丽[1] 刘海[1] 汪杰[1] 郑根稳[1] 潘牧[2] 

机构地区：[1]湖北工程学院化学与材料科学学院,孝感432000 [2]武汉理工大学材料复合新技术国家重点实验室,湖北燃料电池重点实验室,武汉430070

出　　处：《材料导报》2017年第2期33-36,共4页Materials Reports

基　　金：国家自然科学基金(21476178);教育部博士基金(20130143130001);湖北省自然科学基金(2015CFC769)

摘　　要：采用溶胶-凝胶法结合二次高温烧结技术,制备了锰系钙钛矿催化剂。利用XRD和EDS对催化剂的物相与元素组成进行了分析,并利用电化学分析方法研究了催化剂的氧还原催化性能。XRD与EDS结果表明,N_2气氛二次烧结不改变La_(0.7)Sr_(0.3)MnO_3物相组成,但NH3气氛二次烧结会造成La_(0.7)Sr_(0.3)MnO_3分解。电化学结果表明,N_2气氛二次烧结催化剂的氧还原催化活性高于NH3气氛二次烧结催化剂,其氧还原起始电势与极限电流分别为0.028V(vs.Hg/HgO)和2.181mA·cm^(-2)(2 000r/min)。Herein, manganese-based pervoskite oxide was prepared by a sol-gel method combined with secondary sintering technology, and then characterized by means of XRD and EDS to analyze its phase and element composition, electrochemical measure- ment to investigate its catalytic activity for oxygen reduction reaction. XRD and EDS results showed that the phase of La0. 7 Sr0. 3 MnOa remained intact after secondary sintering treatment under N2 atmosphere, while was destroyed under NHa atmosphere. The electro- chemical results showed that the catalytic activity of the Catalyst prepared under Nz atmosphere for oxygen reduction reaction is higher than that of catalyst prepared under NHa atmosphere. The onset potential for oxygen reduction and limited current density are 0. 028 V （vs. Hg/HgO） and 2. 181 mA· cm-2 （2 000 r/mim）, respectively.

关 键 词：二次烧结 LA0.7SR0.3MNO3 氧还原反应 催化活性 

分 类 号：TM911.4[电气工程—电力电子与电力传动]