聚乙烯吡咯烷酮改进TiO_2薄膜的可见光增强氧敏特性  

Improvement of Oxygen-Sensing Properties of Sol-Gel TiO_2 Film under Visible Light by Polyvinyl Pyrrolidone

作　　者：高世安[1] 冼爱平[1] 曹丽华[1] 谢荣才[1] 尚建库[1] 

机构地区：[1]中国科学院金属研究所

出　　处：《传感技术学报》2008年第9期1481-1486,共6页Chinese Journal of Sensors and Actuators

基　　金：国家重点基础研究发展计划(973)的资助(2006CB601201)

摘　　要：室温下工作的半导体气敏材料是一个有吸引力的研究方向。本文以钛酸四丁酯和乙醇胺为主要原料,用溶胶-凝胶法在氧化铝陶瓷片上制备了一种TiO2气敏膜。在可见光照射下,这种气敏膜在室温附近就有明显的可见光增强氧敏性;通过不同溶胶体系的对比,溶胶中添加聚乙烯吡咯烷酮(PVP),烧结后的TiO2膜光增强氧敏性最好,但在添加PVP的同时再添加柠檬酸,则光增强氧敏性下降;扫描电镜下观察,添加PVP的溶胶烧结后获得一种多孔结构的TiO2膜;而不加PVP,或添加PVP的同时再添加柠檬酸的溶胶烧结后获得的是一种连续,致密和有微裂纹的的TiO2膜。对上述PVP促进多孔结构形成的机理进行了分析,最后对半导体可见光增强气敏性的原理和气敏材料改进的方法进行了简要的讨论。Reducing the sensing temperature of semiconductor oxides to room temperature has been actively pursued recently. In present work, the TiO2 gas sensing thin film was prepared on the alumina substrate by a sol-gel method, in which the major raw materials were the tetrabutylorthotitanate （Ti（OBu）4） and ethanolamine （EA）, while the main additive was polyvinyl pyrrolidone （PVP）. The TiO2 thin film showed a strong oxygen-response under visible light at room temperature, when only PVP was the additive in the sol-gel solution. The oxygen-response of the TiO2 thin film was weak if both PVP and citric acid （CA） were added into sol-gel or without PVP. It was found that the TiO2 thin film was porous when only PVP was added into the sol-gel and the thin film was continuous and compact when both PVP and CA were added or without PVP. The effects of the porous structure and light were discussed, and the future directions were suggested for further improving the gas sensing properties of TiO2 thin films.

关 键 词：TIO2 半导体气敏材料 光催化 氧探头 溶胶-凝胶法 

分 类 号：TP212.2[自动化与计算机技术—检测技术与自动化装置]