【摘要】 利用高温固相反应法和溶胶-凝胶法制备了La0.75Sr0.25Cr0.5Mn0.5O3钙钛矿复合氧化物粉体。采用XRD,TEM对粉体物相组成及颗粒形貌进行表征,并以制备的两种粉体作为敏感材料分别制成管状传感器,测试了其NO2气敏性能。结果表明:采用高温固相反应法和溶胶-凝胶法在不同焙烧温度下,均可制得单相La0.75Sr0.25Cr0.5Mn0.5O3粉体,采用溶胶-凝胶法在800℃焙烧2 h得到的粉体粒径约为20 nm;传感器输出电动势信号对NO2浓度之间呈良好的线性关系;溶胶-凝胶法制得粉体的气敏性能优于高温固相反应法制得粉体的气敏性能。更多还原

【Abstract】 La0.75Sr0.25Cr0.5Mn0.5O3 powders were prepared by high-temperature solid reaction and sol-gel method,respectively.The samples were characterized by XRD and TEM.Electrochemical sensors using tubular MSZ and the perovskite-type LSCM sensingelectrode(SE),which were prepared at 1200 and 800 ℃ for 2 h,were fabricated and examined for NO2 detection,respectively.The results showed that all the methods can get a single-phase after calcined at different temperatures and the particle diameters was about 20 nm after calcined at 800 ℃ for 2 h by sol-gel method.The results showed that all devices were extremely sensitive to NO2 and the EMF varied linearly as a function of the concentration of NO2(0～463×10-4%).The one using La0.75Sr0.25Cr0.5Mn0.5O3 synthesized by sol-gel method had better sensing properties.更多还原