水热合成CdS/TiO_2复合光催化剂及其催化分解硫化氢制氢

以沉淀-水热法制备了系列CdS/TiO2复合光催化剂,采用紫外-可见光漫反射光谱、X射线衍射、扫描电子显微镜和表面光电压谱等方法对催化剂进行了表征,考察了CdS与TiO2的摩尔比和水热温度对CdS/TiO2复合光催化剂在波长大于400nm的可见光下光催化分解硫化氢制氢性能的影响。表征结果显示,该复合光催化剂表现出CdS与TiO2共有的光学性能,TiO2的吸收边向可见光区移动,扩展了光响应范围;CdS与TiO2得到很好的复合,可有效降低光生电子-空穴对的复合几率。实验结果表明,与纯CdS催化剂相比,CdS/TiO2复合光催化剂的光催化活性明显提高,CdS与TiO2摩尔比为0.5、水热温度为200℃时制得的CdS/TiO2复合光催化剂的性能最佳,产氢速率可达4.96mmol/(h.g)。

Decomposition of H2S to Produce H2 over CdS/TiO2 Composite Photocatalysts Prepared by Hydrothermal Method

CdS/TiO2 composite photocatalyst for decomposition of H2S to produce H2 under visible light with wavelength more than 400 nm was prepared by hydrothermal method using TiO2-P25,Na2S and Cd(NO3)2 as materials.The catalyst was characterized by means of SEM,XRD,UV-Vis DRS and SPS.Influences of hydrothermal temperature and mole ratio of CdS to TiO2 on performance of CdS/TiO2 composite photocatalysts were studied.The composite photocatalyst exhibited common optical properties of CdS and TiO2,widened the photo response range and inhibited recombination of photogenerated electron-hole pairs.The catalytic activities of CdS/TiO2 composite photocatalysts were higher than that of sole CdS.When mole ratio of CdS to TiO2 was 0.5,and hydrothermal temperature was 200 ℃,the activity of prepared composite photocatalyst was best and the hydrogen production rate was 4.96 mmol/(h·g).