【摘要】 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%。更多还原

【Abstract】 Nano-TiO2 film was deposited in diatomite-based porous ceramics by the hydrolysis precipitation with TiCl4 as raw material,ammonia 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 of formaldehyde.The results indicate that with the increase of the heat treatment temperature,the film crystal trans-form from anatase into rutile,and TiO2 grain size increase from 6.5 nm(350 ℃) to 52.8 nm(1 000 ℃);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.更多还原