与粉体催化剂相比,薄膜催化剂具有操作简单、回收便利、可重复利用等特点。实验分别利用微乳液法和蒸发诱导自组装法在锌箔基底上制备了ZnO多级结构微米花以及ZnO微米棒2种结构薄膜。采用x射线衍射仪、扫描电子显微镜对其物相、形貌进行了表征。以罗丹明B溶液为研究体系,采用荧光分光光度计和高效液相色谱仪考察了2种薄膜催化剂对罗丹明B溶液的光催化性能。实验表明:微乳液法制备的ZnO多级结构微米花薄膜催化剂与蒸发诱导自组装法制备的ZnO微米棒薄膜催化剂相比具有更好的光催化性能。在紫外光(300w)照射下,微米花薄膜催化剂3h可使罗丹明B溶液的降解率达到97%,远高于微米棒薄膜催化剂的87%,微米花薄膜催化剂重复使用5次后,其降解率只从最初的97%降到90oA,具有较好的光催化稳定性。
Compared to powdered catalysts, the micro/nanostructure thin film catalysts have some features such as simple oper- ation, easy recycling and good reusability. In this paper, zinc oxide (ZnO} hierarchical microflowers and ZnO microrods thin film were prepared by a microemulsion method and an evaporation induced self-assembly method respectively. The crystallinity and morphology were characterized by X-ray diffraction and scanning electron microscopy, respectively. The photocatalytic properties of these two different ZnO structures were investigated by using Rhodamine B (RhB) solution as a degradation sys- tem, and detected by photoluminescence and high perfornance liquid chromatograph techniques. The results show that ZnO hi- erarchical microflower films exhibit better photocatalytic properties than the microrod film. The degradation rate of RhB solu- tion is achieved to be 97% for 3 h when ZnO hierarchical microflower film is used as a photocatalyst. However, the degradation rate for ZnO microrod film is only 87 ~ under the same condition. Moreover, the RhB degradation rate is reduced from initial 97% to 90% when the ZnO hierarchical microflower film catalyst is reused for 5 cycles, indicating that the hierarchical struc- ture film has a good photocatalytic stability.