摘要
固体氧化物燃料电池(solid oxide fuel cell,SOFC)阴极材料的高稳定性、高催化性能是其获得商业化应用的前提。尖晶石氧化物具有良好的稳定性与兼容性,这使得其成为最具发展潜力的SOFC阴极材料之一。本文通过Mg掺杂对尖晶石氧化物Mn_(1.5)Cr_(1.5)O_(4)阴极材料进行改性处理,研究了Mg掺杂量对Mn_(1.5)Cr_(1.5-x)Mg_(x)O_(4)(x=0,0.075,0.150,0.225)阴极材料微观结构、物相组成、电导率、热膨胀系数及其作为对称电池阴极时电化学性能等方面的影响。结果表明,当Mg掺杂量x为0.150时,Mn_(1.5)Cr_(1.35)Mg_(0.15)O_(4)具有最大的电导率和最小的极化阻抗,在800℃下分别可达0.168 S/cm和1.84Ω·cm^(2),表明适量的Mg掺杂不仅提高了Mn_(1.5)Cr_(1.5)O_(4)阴极材料的电化学性能,而且还能加快氧气分子在其表面的吸附解离过程。
The high stability and catalytic performance of cathode materials for solid oxide fuel cells(SOFC)are prerequisites for the commercial application of SOFC.Spinel oxides,with their excellent stability and compatibility,have become one of the most promising cathodes for SOFC.This study modified the spinel oxide Mn_(1.5)Cr_(1.5)O_(4)cathode material through Mg-doping.The effects of Mg-doping amount on the microstructure,phase composition,conductivity,thermal expansion coefficient,and electrochemical performance of Mn_(1.5)Cr_(1.5-x)Mg_(x)O_(4)(x=0,0.075,0.150,0.225)as a symmetrical cell cathode were investigated.The results demonstrate that when the Mg-doping amount x is 0.150,Mn_(1.5)Cr_(1.35)Mg_(0.15)O_(4)exhibits the highest conductivity and the lowest polarization impedance,reaching 0.168 S/cm and 1.84Ω·cm^(2)at 800℃,respectively.This indicates that the appropriate amount of Mg-doping not only enhances the electrochemical performance of Mn_(1.5)Cr_(1.5)O_(4)but also accelerates the adsorption and dissociation process of oxygen molecules on its surface.
作者
季炤宇
马奔
周盈科
Ji Zhaoyu;Ma Ben;Zhou Yingke(State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China;College of Science,Wuhan University of Science and Technology,Wuhan 430081,China)
出处
《武汉科技大学学报》
CAS
北大核心
2023年第4期257-264,共8页
Journal of Wuhan University of Science and Technology
基金
国家自然科学基金青年基金项目(51902230)
国家自然科学基金面上项目(51974209).
作者简介
季炤宇(1996-),男,武汉科技大学硕士生,E-mail:1285628522@qq.com;通讯作者:马奔(1984-),男,武汉科技大学副教授,博士.E-mail:maben@wust.edu.cn。
