在微波条件下采用Sol-Gel法制备了纳米TiO2光催化剂,通过XRD,TEM,BET,荧光吸收等考察了焙烧温度对TiO2结构的影响。以光催化降解苯酚反应为探针,考察了微波对于TiO2活性的影响。结果表明,微波用于凝胶合成能够显著提高TiO2的光催化活性,降低由锐钛矿型向金红石型的转化温度。这主要归因于微波加热可以提高反应物的分散度,在低温焙烧就可得到高结晶度的锐钛矿型TiO2,且晶粒均匀。
A new TiO2-based photoeatalyst was synthesized by Sol - Gel method under microwave radiation and was denoted as TiO2-MW. During phenol photocatalytie degradation in aqueous solution, the TiO2 -MW exhibited much higher activity than the corresponding TiO2-DC obtained via direct calcination. XRD, TEM, BET, and fluorescence spectra revealed that the preparation of TiO2 under microwave radiation could affect the TiO2 structure. The promoting effect of microwave could be attributed to the uniform nanoparticles and increasing surface area which facilitated the adsorption of both the UV light and the phenol molecules. It could also be attributed to the enhancement of the crystallization degree of anatase in TiO2 under low calcination temperature. As well known, the anatase phase was more active than the rutile in photocatalysis and the increase of anatase crystallization degree was favorable for its photocatalytie activity.