CdS/ZnO复合光催化剂降解亚甲基蓝的研究

Studies on methylene blue degradation using CdS/ZnO compound Photocatalysts

利用水热法合成具有层级片状结构的ZnO纳米片,再利用原位生长法得到不同CdS复合比的CdS/ZnO复合光催化剂。采用X射线粉末衍射(XRD)、紫外-可见漫反射吸收光谱(UV-Vis)等手段对所制备的光催化剂进行了表征,并考察了CdS/ZnO在可见光下光催化降解亚甲基蓝溶液的催化性能。研究表明,经CdS修饰后,其光催化性能明显提高。当亚甲基蓝初始浓度为5mg·L^(-1),催化剂用量为2g·L^(-1)时,光反应240min后,亚甲基蓝的降解率高达96%。同时,对CdS/ZnO复合光催化剂可见光降解亚甲基蓝的催化机理进行了分析。

Hierarchical ZnO composed of nanosheets structures were fabricated through a hydrothermal method. Afterwards, CdS loaded ZnO（ CdS/ZnO） were obtained by in-situ growth method. The as-prepared samples were characterized by X-ray diffraction （XRD） ,UV-Vis diffuse reflectance spectra（DRS）. The photocatalytic performance of ZnO/CdS photocatalysts were evaluated by the photodegradation of methylene blue（ MB） under the visible light（ X〉420nm） irradiation. The results indicate that after modifica-tion with CdS,the composite photocatalysts exhibit higher photocatalytic activity compared with pure ZnO. The photocatalytic activity of 5% CdS/ZnO reached 96% in MB aqueous solution（ 5 mg · L^-1 ） containing 2g · L^-1 catalyst under visible-light irradiation. Final-ly the photocatalytic mechanism for MB degradation by CdS/ZnO under visible light irradiation was also presented.