热解法制备纳米SnO2及其气敏性能研究

作为一种n型金属氧化物半导体，SnO2由于具有寿命长、灵敏度高和成本低等特点而一直是电阻式气敏传感器研究的热点．由于SnO2材料的气敏效应是晶粒表面控制型的，因此，SnO2的传感性能对其粒径和比表面积的大小有很强的依赖性．改进SnO2制备方法，提高其气敏效应一直是气敏传感器研究的热点．目前，文献报道的方法大多是以SnCl4为原料制备SnO2，而以其它锡盐为原料的研究则很少。本文以SnC2O4为原料，通过低温直接热解SnC2O4制得SnO2．所得产物具有粒径小、分布均匀和比表面积大的特点，且具有良好的酒敏特性，该产物的红外吸收出现明显的红移现象。

Synthesis of Nano-SnO2 Through Pyrolysis Method and Its Gas Sensitivity Property

Nanosized SnO2 powders were synthesized by using the direct pyrolysis means from SnC2O4 .The specimens were characterized by TEM, XRD, TG-DTA, FTIR and BET. TEM and XRD showed that the SnO2 crystallines were less than 8 nm in diameter together with a narrow particle size distribution. BET showed that the surface area of SnO2 was 115.2 m2/g. FTIR spectra revealed that the absorptions of Sn—O and —OH bonds in SnO2 ultrafine powders were red-shifted and broadened. According to the curve of TG-DTA, SnC2O4 transformed into SnO2 completely after being calcined at 250 ℃. Further gas sensing experiments testified that the response and recovery times to C2H5OH were shorter than those obtained by the conventional precipitation method.