掺杂Ce的纳米ZnO对酸性染料降解作用及结构表征

Degradation Effect of Ce-Doped ZnO on Acid Dyes and Structure Characterization

通过掺杂稀土元素Ce制备Ce-ZnO催化剂,以甲基橙溶液(3×10^-5 mol·L^-1)为酸性染料代表,研究Ce-ZnO催化剂在自然光和紫外光下对甲基橙溶液的光催化降解效果,并表征其结构。结果表明:掺杂Ce有效地提高了纳米ZnO在自然光下和紫外光下催化降解甲基橙溶液能力,其中催化3 h时降解甲基橙溶液顺序为:紫外光下Ce-ZnO催化剂(78.98%)>自然光下Ce-ZnO催化剂(55.52%)>紫外光下ZnO(49.63%)>自然光下ZnO(9.13%)。甲基橙溶液在紫外光下经Ce掺杂量为2%~3%的Ce-ZnO催化降解3 h,降解率达到75%以上。扫描电镜分析显示Ce-ZnO催化剂表面具有蜂窝结构,X-射线衍射分析表明Ce的掺入促使ZnO(101)衍射峰向小角度移动,并有Ce(OH)3相关弱衍射峰出现。能谱分析确定Ce-ZnO催化剂中Zn元素平均含量为41.73%,Ce元素平均含量为0.58%。掺杂稀土元素Ce的纳米ZnO有进一步开发用于工业废水处理的应用前景。

The Ce-ZnO catalyst was prepared by nano ZnO doped with the rare earth element of Ce.In this study,the methyl orange solution(3×10^-5 mol·L^-1)was used to represent the acid dyes,and the photocatalytic degradation of methyl orange solution induced by the Ce-ZnO catalyst under natural light and ultraviolet light was evaluated.Furthermore,the structure characteristic of the Ce-ZnO catalyst was investigated.Results showed that the photocatalytic degradation of nano ZnO on methyl orange solution under either natural light or ultraviolet light was effectively increased after doped with Ce.The degradation order of methyl orange solution catalyzed for 3 h was as follows:Ce-ZnO catalyst under ultraviolet light(78.98%)>Ce-ZnO catalyst under natural light(55.52%)>ZnO under ultraviolet light(49.63%)>ZnO under natural light(9.13%).The result of scanning electron microscope analysis showed formation of honeycomb structures on the surface of Ce-ZnO catalyst.Compared with ZnO,the shift of ZnO(101)diffraction peak to a small angle as well weak diffraction peak related with Ce(OH)3 were observed in the X-ray diffraction analysis.The energy spectrum analysis revealed that the average amounts of Zn and Ce elements in the Ce-ZnO catalyst were 41.73% and 0.58%,respectively.In general,the nano ZnO doped with the rare earth element of Ce could have further application prospect in industrial wastewater treatment.