sol-gel纳米晶二氧化锡薄膜的制备及表征

以SnCl4为原料,采用sol-gel技术,应用间接成胶法,在玻璃片上制备了纳米晶SnO2薄膜及粉体,以其灵敏度、响应时间和工作温度作为评价气敏性能的标准,对制备工艺参数进行了优化,并用DSC-TG、XRD、AFM等手段对样品进行了表征。结果表明,水与乙醇体积比为3:1,草酸与四氯化锡摩尔比为0.3:1,在500℃下退火的薄膜表面平整,平均粒度在20nm左右,且相应的薄膜元件对丙酮蒸气具有良好的选择性和较高的灵敏度、较短的响应时间和较低的工作温度(≈190℃)。

Preparation and Characterization of Nanocrystalline SnO2 Gas Sensitive Thin Film by Sol-gel

Fine nanocrystalline SnO2 gas sensitive thin films on the glass and powder were prepared by the indirect technique of forming colloid of sol-gel process, in which SnCl4 was used as a sort of source material. In order to improve the gas sensitive capability of SnO2 thin film, the technique parameters of preparing were selected and the better conditions of preparing were received. The samples’ thermic weightlessness, morphology and structure were characterized by DSC-TG, XRD, AFM and so on. The result indicate the thin film has a perfect surface with the grain size being around 20 nm and the corresponding gas sensor is found to be of good selectivity to the acetone gas and has the high sensitivity, short response time and low work temperature, when the bulk proportion of water and ethanol is 3:1, the mol ratio of oxalic acid and SnCl4 is 0.3:1, the calcining temperature is 500℃.