焙烧的P-25 TiO2微结构特性和光催化活性

光催化氧化能把有机污染物完全转化为二氧化碳和水，被认是有广泛应用前景的水处理方法1，2]．但是，这一方法真正在污水处理中实际应用，有许多问题仍待解决，其中光催化剂的活性和稳定性需要进一步改善．研究最多的光催化剂是TiO2，影响其催化活性的因素很多3，4]，本工作用XRD、TEM、BET研究了烧结的P－25TiO2微结构特征，并用苯酚光催化降解作探针反应，得到了很有意义的相关信息．1材料和方法1．1催化剂商品P－25TiO2是从Degussa公司购买．样品分别经不同温度和时间焙烧，具体条件见表1．1．2催化剂表征XRD用于测定样品品相…

Microstructure Characteristics and Photoreactivity of Calcined P-25 Tio_2

The microstructural characteristics of P-25 TiO2 photocatalysts calcined at 600, 650,700, 750, 800, 900 and 1000℃ have been studied using XRD, TEM and BET. The photocatalytic activity of the samples were also examined using the degradation of phenol as a model reaction. The results indicate that the calcination significantly affects both microstructural characteristics and photoactivity, and there is an apparent relationship between photocatalytic activity and centain mocrostructural characteristics. Over the range of calcination temperatures and durations studied, the sample calcined at 650℃ for 3 h revealed the highest photoreactivity, which can be ascribed to an improvement in crystallinity on calcination. The increase in the rutile content and grain size caused by the calcination at higher temperatures were observed to decrease the photocatalytic activities of the TiO2 samples.