纳米异质结光催化材料在环境污染控制领域的研究进展

Nano-Heterojunction Photocatalytic Materials in Environmental Pollution Controlling

纳米异质结结合了纳米材料和异质结的优点,在许多领域得到广泛研究。在环境污染控制领域,由于能够克服TiO2光催化剂的量子效率低和不能有效利用可见光等缺点,纳米异质结具有潜在的应用价值。本文首先介绍了与污染控制有关的异质结的基本理论,包括内建电场对光致电荷分离的驱动作用及其作用范围,光照方式、上层半导体厚度、能带和构型对异质结电荷分离方式的影响。然后总结了纳米pn结、nn结、肖特基结、半导体与碳材料构成的纳米异质结光催化材料在环境污染控制领域的进展,并对其发展趋势作了展望。

Nano-heterojunctions, which integrate the advantages of nano-materials and heterojunctions, have attracted wide interests in many areas. In environmental pollution controlling area, nano-heterojunctions possess the potential application, because they can overcome the two obstacles of TiO2 photocatalyst： the dissatisfactory quantum efficiency and the neglectable utilization of visible light. This review introduces the basic mechanism of nano- heterojunction related to environmental pollution controlling, including the driving force of inner electric field to photogenerated charge separation and its active region, the effect of illumination, the thickness of top semiconductor, energy bands and structure type on photogenerated-charge-separation mode of heterojunction. The progress of pn junction, nn junction, Schottky junction, and heterojunctions of semiconductor with carbon materials in environmental pollution controlling is summarized. The future developing perspectives are also presented.