纳米二氧化钛表面包覆改性及光催化性能研究

A study on the surface modification and photocatalytic properties of nanometer TiO_2

通过Cr2O2-7的还原反应研究了Fe3+和SiO2包覆对锐钛型纳米二氧化钛光催化性能的影响,以及氢氟酸溶液对SiO2包覆层的刻蚀作用.结果表明:铁包覆可提高纳米二氧化钛的光催化性能;当Fe2O3与TiO2的质量比10%时,Fe3+包覆纳米二氧化钛光催化性能最好;SiO2包覆能很好地屏蔽纳米二氧化钛的光催化功能;采用2.5%的氢氟酸溶液可以除去SiO2包覆层,恢复纳米二氧化钛的光催化功能.

The effects of photocatalytic properties of the nanometer anatase TiO2 coated with Fe(Ⅲ) and silicon dioxide and the etching of silicon dioxide coating with hydrofluoric acid have been investigated using the reducing reaction of Cr2O2-7. The results show that the Fe(Ⅲ) coating can improve the photocatalytic property of the TiO2, when Fe2O3/TiO2 ratio is 10% in the TiO2 coated with Fe(Ⅲ), the TiO2 exhabits better photocatalytic property, while the coating of SiO2 can shield the photocatalytic property of the TiO2, the photocatalytic property of the TiO2 coated with Fe(Ⅲ) and SiO2 is worse than TiO2. But the TiO2 coated with SiO2 exhabits better photocatalytic property, when it is etched for 2 hour in the solution of hydrofluoric acid of 2.5%. 