高能(001)晶面外露的锐钛矿TiO2微球的水热制备及其气敏性能研究

The Hydrothermal Preparation and Gas Sensing Properties of Anatase TiO_2 Microspheres with Exposed High-Energy(001) Crystal Facets

采用一步水热法制备了由高能(001)晶面外露的锐钛矿相单晶组装而成的TiO_2微球.通过反应体系p H值的调控可以对TiO_2微球的微观形貌进行调控.对TiO_2微球的生长机理进行了分析.结果表明:适中的氢氟酸分子浓度对高能(001)晶面的稳定至关重要.进一步的研究表明,得益于高能(001)晶面的外露以及独特的分级形貌,这种TiO_2微球对丙酮表现出了优异的气敏性能.

TiO_2 microspheres composed of anatase single crystal with exposed high-energy( 001) crystal facets are fabricated by a one-pot hydrothermal method. The micro-morphology of the TiO_2 microspheres can be tuned by the pH value of reaction system. The growth mechanism of the TiO_2 microspheres is analyzed,. The results show that moderate concentration of hydrofluoric acid is very important for the stability of high energy( 001) crystal surface.Further studies indicate that the TiO_2 microspheres show excellent gas sensing performance towards acetone,due to the exposing of high-energy( 001) crystal facets and unique hierarchical morphology.