论文部分内容阅读
用高温固相反应法合成了非化学计量组成的Ba1.03Ce0.5Zr0.4La0.1O3-α质子导体.粉末X射线衍射(XRD)结果表明,该材料为单一钙钛矿型BaCeO3斜方晶结构,在高温下、CO2或水蒸气气氛中具有较高的稳定性.扫描电子显微镜(SEM)观察分析表明,材料经1550℃烧结20h非常致密.在500～900℃温度范围内,用交流阻抗谱技术测定了材料在湿润氢气和湿润空气气氛中的电导率;用气体浓差电池方法测定了材料在湿润氢气、湿润空气气氛中和氢-空气燃料电池条件下的离子迁移数,研究了材料的离子导电特性,并与化学计量组成的BaCe0.5Zr0.4La0.1O3-α材料进行了比较.结果表明,在500～900℃温度范围内、湿润氢气气氛中,Ba1.03Ce0.5Zr0.4La0.1O3-α材料的质子迁移数为1,是一个纯质子导体.在湿润空气气氛中,材料的氧离子迁移数为0.688～0.170,质子迁移数为0.218～0.017,是一个氧离子、质子和电子空穴的混合导体.在氢-空气燃料电池条件下,材料的离子(氧离子+质子)迁移数为0.990～0.796,是一个氧离子、质子和电子的混合导体.与化学计量组成的BaCe0.5Zr0.4La0.1O3-α材料相比较,在相同实验条件下非化学计量组成的Ba1.03Ce0.5Zr0.4La0.1O3-α材料具有较高的电导率和离子迁移数.
Ba1.03Ce0.5Zr0.4La0.1O3-α proton conductor with non-stoichiometric composition was synthesized by high temperature solid-state reaction.The results of XRD showed that the material was a single perovskite BaCeO3 orthorhombic structure , Under high temperature, CO2 or water vapor atmosphere has a high stability. Scanning electron microscopy (SEM) observation and analysis showed that the material sintered at 1550 ℃ for 20h very dense in the temperature range of 500 ~ 900 ℃, the use of alternating current impedance spectroscopy Technology was used to determine the conductivity of the material in wet hydrogen and humid air atmosphere. The ion mobility of the material in wet hydrogen atmosphere, humid air atmosphere and hydrogen-air fuel cell was measured by gas concentration cell method. Ion conductivity, and compared with the stoichiometric composition of BaCe0.5Zr0.4La0.1O3-α.The results show that in the hydrogen atmosphere at a temperature of 500-900 ℃, Ba1.03Ce0.5Zr0.4La0.1O3 -α material is a pure proton conductor, the oxygen ion migration number is 0.688 ~ 0.170 and the proton migration number is 0.218 ~ 0.017 in wet air atmosphere, which is an oxygen ion, proton and electron vacancy Point of the mixed guide Under hydrogen - air fuel cell conditions, the material ions (oxygen ions + protons) migration of 0.990 ~ 0.796, is a mixed oxide of oxygen ions, protons and electrons with the stoichiometric composition of BaCe0.5Zr0.4La0.1O3 -α material, Ba1.03Ce0.5Zr0.4La0.1O3-αhave higher conductivity and ion mobility under the same experimental conditions.