N_2气氛下SnO_2的烧制及其光催化性能研究

Study on SnO_2 Burning and its photocatalytic performance under N_2 atmosphere

扩展稳定宽带隙半导体吸收带边是提高其光能利用率的有效方法之一。采用溶胶-凝胶法,在空气和N_2中分别制得SnO_2和SnO_2(N_2)光催化剂。X射线衍射和BET结果表明SnO_2和SnO_2(N_2)的晶型和比表面积基本相同。紫外-可见漫反射分析结果表明SnO_2和SnO_2(N_2)试样的吸收带边分别为352和388nm,SnO_2(N_2)试样的吸收带边有明显的红移,且光催化降解亚甲基蓝的活性较高。N_2条件下对SnO_2带隙进行调控,相比于普遍采用的H2,该方法更安全,这为后续宽带隙半导体表面氧空位浓度的调变提供了实验基础。

One of the most effective way to improve the solar energy utilization efficiency of wide band gap semicon- ductor is to extend the band edge. SnO2 and SnO2 （N2） photoeatalyst were respectively prepared in air and N2 by sol gel method. XRD and BET analysis revealed that SnO2 （N2） and SnO2 had similar crystal form and comparative surface area. The UV-Vis diffuse reflection spectrum indicated that the adsorption band edge of SnO2 and SnO2 （N2） were 352 and 388nm,respectively,the absorption band edge of SnO2 （N2） had obvious red shift, and the photoeatalytic degradation of methylene blue was higher. The band edge of SnO2 was regulated under the N2 atmosphere, which was more secure than the popular H2 system. The experiment results provided a much easier and more secure way to tune the surface oxygen vacancies of the wide band gap semiconductors.