SnO_2气敏材料动态测试方法研究

Study of Dynamic Measurement of SnO_2 Gas Sensitive Materials

气敏材料的气敏特性来源于气体在材料表面的吸附和表面反应过程。传统的气敏材料测试方法仅仅测试材料在与气体接触前后电阻的变化 ,只能反映气体吸附的结果 ,而不能反映吸附和解吸的动态过程。本文提出了一种新的气敏材料测试方法 ,在间断加热的过程中测试气敏材料的动态特性。由于工作温度的变化 ,气敏材料的电阻按一定规律变化。不同气体在材料表面有不同的吸附机理和活化能 ,温度变化时气体在材料表面的反应平衡发生变化。根据这一原理可以得到气体的特征谱线 ,从而使气敏材料具有优良的选择性。

Gas sensitive materials have gas sensitive characteristics because of the adsorption and reaction of gases on the surface of materials. The general measurements record only the change of materials' resistance before and after meeting gases. It reflects only the results, not the dynamic process of adsorption. We developed a new method to test the dynamic characteristics of gas sensitive materials, and could get unique curve for different gases. By this method, we can get high selectivity gas sensors.