氧化石墨烯/钒钛酸复合材料的制备及湿敏性能研究

Preparation and Humidity Sensitive Properties of Graphene Oxide/Vanadium Titanium Acid Thin Film

通过Hummers法制备氧化石墨后进行超声分散,得到分散均匀的氧化石墨烯(GO)分散液,物理复合滴涂制备氧化石墨烯/钒钛酸薄膜并对其感湿性能进行了研究,并通过交流与直流方法对其感湿机理进行了深入探究。结果表明:氧化石墨烯/钒钛酸复合膜的湿敏性能优于氧化石墨烯和钒钛酸单层膜,该湿敏薄膜的湿滞为8.3%RH,灵敏度变化2个数量级,响应时间为8 s,还原时间为10 s,曲线线性度良好。材料在低湿阶段主要表现为电子导电,中高湿阶段为电子导电和离子导电同时存在,高湿阶段主要表现为离子导电。

Graphite oxide was prepared from flake graphite by Hummers method. Graphene oxide（GO） was prepared after super-sonic oscillation of graphite oxide.Graphene oxide/vanadium titanium acid thin film was prepared by physical drop coating method, and its humidity sensing properties was studied. The humidity sensing mechanism of the GO/VTi thin film sensor was analyzed by AC and DC methods. Experimental results showed that the humidity sensing properties of GO/VTi thin film was better than that of single layer GO thin film or single layer VTi thin film; The hysteresis of the humidity sensitive thin film was 8.3% RH; The sensitivity was two orders of magnitude, the response time was 8 s and recovery time was 10 s; The linearity was ideal. The sensor mainly manifested as electronic conduction in low humidity stage, electronic conduction and ionic conduction both existed in medium high humidity stage. In high humidity stage, it manifested as ionic conduction.