sol-gel法制备Yb_2O_3掺杂纳米SnO_2及气敏性能研究

以SnCl_4·5H_2O与柠檬酸为原料,采用sol-gel法制备了掺杂质量分数w(Yb_2O_3)为0~1.0%的Yb_2O_3-SnO_2纳米粉体。利用XRD、TEM等测试手段分析了粉体的微观结构,采用静态配气法测试了由所制粉体制成的气敏元件对NO_2、Cl_2、H_2、H_2S、乙醇、甲醛等气体的气敏性能。结果表明:用该法得到的粉体颗粒粒径小,且均匀;工作温度为100℃时,由掺杂w(Yb_2O_3)为0.4%的SnO_2粉体,在烧结温度600℃制得的气敏元件,对体积分数为30×10–6的NO_2的灵敏度最高可达18224,且该元件具有较好的响应–恢复特性,响应时间和恢复时间分别是20s和15s。

Preparation of Yb2O3-doped SnO2 nanopowder by sol-gel method and its gas sensing properties study

Yb2O3-doped SnO2 nanopowder containing 0~1.0% (mass fraction) of Yb2O3 was prepared from SnCl4·5H2O and citric acid by the sol-gel method, and its microstructure was characterized with XRD and TEM. Gas sensors were fabricated from the prepared nanopowder, and the gas sensing property of them to NO2, Cl2, H2, H2S, alcohol and formaldehyde was measured via the static volumetric method. The results indicate that the particle size of obtained nanopowder is small and constant. For the gas sensor fabricated from the nanopowder containing 0.4% of Yb2O3 under a sintering temperature of 600 ℃, its maximum sensitivity to NO2 (volume fraction: 30×10–6) reaches 18 224 at a working temperautue of 100 ℃. Moreover, such sensor exhibits superior response-recovery characteristics, and its response time and recovery time are 20s and 15s, respectively.