热处理温度对纳米TiO2薄膜光催化性能的影响（英文）

以TiCl4为原料,氨水为沉淀剂,采用水解沉淀法在硅藻土基多孔陶瓷上负载了TiO2薄膜。通过热重–差示扫描量热分析、X射线衍射对经不同温度热处理的样品进行了表征,探讨了热处理温度对TiO2晶相、晶粒尺寸等因素的影响。以甲醛为目标降解物,考察了热处理温度对TiO2光催化性能的影响。结果表明:随着热处理温度的升高,薄膜由锐钛矿型转变为金红石型,TiO2晶粒尺寸由6.5 nm(350℃)增加到52.8 nm(1 000℃);经750℃热处理的薄膜组成中出现金红石相,温度升至1 000℃,锐钛矿型TiO2完全消失;经550℃热处理的TiO2光催化效果最好,在1 m3环境仓内,8 W紫外灯下光照240 min,初始浓度0.526 mg/m3的甲醛去除率达到95.2%。

Influence of Heat Treatment Temperature on Photocatalytic Properties of Nano-TiO2 Film

Nano-TiO2 film was deposited in diatomite-based porous ceramics by the hydrolysis precipitation with TiCl4 as raw material,ammoma as precipitating agent.Samples heat treated at different temperatures Were characterized by thermogravimetry-differential scanning thermal analysis and X-ray diffraction.The influence of the heat treatment temperature on TiO2 crystal phase,grain size and other factors was investigated.The effects of heat treatment temperature to photo-catalysis property of TiO2 film were also inspected by degradation offormaldehvde.The results indicate that with the increase of the heat treatment temperature,the film crystal transform from anatase into mtile,and TiO2 grain size increase from 6.5nm (350℃) to 52.8nm (1000℃)；For samples heat treated at 750℃,the content of TiO2 film occurs rutile TiO2；The temperature was improved to 1 000℃,anatase TiO2 disappeared entirely.When TiO2 film is heat treated at 550℃,the removal rate of formaldehyde with initial concentration 0.526 mg／m3 is the maximum,and reaches 95.2％in 1 m3 environment chambers under 8 W ultraviolet lamp irradiation for 240 min.