混晶TiO_2光催化剂的制备及机理研究

Synthesis and Photocatalytic Mechanisms of the Mixed-Phase TiO_2 Photocatalysts

本文总结了混晶TiO2光催化剂的各种制备方法,并将其分为两大类:一类是原位生成混晶,如水热法、溶剂热法、溶胶-凝胶法、微乳液-水热联用方法等;另一类是对两种晶型TiO2材料进行物理混合或对锐钛矿进行高温煅烧,如溶剂混合-煅烧法、高温煅烧法等。其中,后者操作简单易行、对设备要求不高,但获得的混晶TiO2易产生硬团聚,严重影响其光催化性能;在实际应用中前者制备的TiO2材料更具优势。同时,本文还对混晶TiO2光催化机理的研究历程进行了总结,并对其中存在的争议进行了评述。最后,展望了混晶TiO2光催化剂在环境和能源领域中的应用。

This review summarizes the preparation methods of mixed-phase TiO2 photocatalysts. Two main lines of fabrication have been followed： one is preparation of mixed-phase TiO2 in situ （e. g. hydrothermal method, solvothermal method, sol-gel method and microemulsion-mediated hydrothermal method, etc. ）, and the other is physical mixing of different phases of TiO2 or calcinations under high temperature （ e. g. solvent mixing and calcination treatment, calcination under high temperature, etc. ）. The latter has fewer requirements on the equipments, hut the produced TiO2 nanoparticles tend to be aggregates, which affects the photocatalytic performance of TiOz materials seriously. The former has more advantages in practical applications. At the same time, this review summarizes and remarks the researches on photocatalytic mechanisms of the mixed-phase TiO2. Furthermore, the applications of the mixed-phase TiO2 photocatalysts in environmental and energy fields are also prospected.