摘要
以高温固相反应法制备了BaCe0.8Zr0.1La0.1O3-α陶瓷,用粉末X-射线衍射(XRD)和扫描电镜(SEM)对其晶体结构和断面形貌进行了表征。以陶瓷材料为固体电解质、多孔性铂为电极,用交流阻抗谱技术测定了材料在500～900℃下不同气体气氛中的电导率;用气体浓差电池方法测定了材料在干燥空气和湿润空气中的离子迁移数;研究了材料的离子导电特性。结果表明,该陶瓷材料为单一钙钛矿型BaCeO3斜方晶结构。在500～900℃下,干燥和湿润的氧气、空气和氮气中,材料的电导率随着温度升高和氧分压增大而增大。在干燥的空气中,材料的氧离子迁移数为0.06～0.17,表现为氧离子与电子空穴的混合导电性,其中,电子空穴导电为主导。在湿润的空气中,材料的质子迁移数为0.52～0.01,氧离子迁移数为0.14～0.27,表现为质子、氧离子和电子空穴的混合导电性,其中,在500～550℃下,质子导电为主导;高于550℃,电子空穴导电为主导。
BaCe0.8Zr0.1La0.1O3-α ceramic was prepared by high temperature solid-state reaction.Phase composition and fracture morphology of the material were characterized by using XRD and SEM,respectively.Using the ceramic as solid electrolyte and porous platinum as electrodes,conductivity of the material in different gases was measured by ac impedance spectroscopy method in the temperature range of 500～900 ℃,ionic transport number was measured by gas concentration cell method in dry air and wet air,respectively.Ionic conduction was researched.The results indicate that the ceramic is of a single orthorhombic phase of perovskite-type BaCeO3.In the temperature range of 500～900 ℃,the conductivity of the material in the different gases is increased as the temperature rises and oxygen partial pressure increases.In dry air,the oxide ionic transport numbers are 0.06～0.17,the material exhibits mixed conduction of oxide ion and electronic hole,and the electronic hole conduction is predominant.In wet air,the protonic transport numbers are 0.52～0.01,the oxide ionic transport numbers are 0.14～0.27,the material exhibits mixed conduction of proton,oxide ion and electronic hole.The protonic conduction is predominant from 500～550 ℃,but the electronic hole conduction is predominant above 550 ℃.
出处
《化学研究与应用》
CAS
CSCD
北大核心
2011年第8期1051-1056,共6页
Chemical Research and Application
基金
江苏省高校“青蓝工程”项目资助
江苏省高校自然科学基金(07KJB150126)项目资助
