多壁碳纳米管修饰的CdS/TiO_2复合光催化材料的制备及其光解水制氢特性

摘要

The CdS/TiO_2 photocatalytic composites containing different amounts of CdS were fabricated using sol-gel method with P25 TiO_2 as the raw material. The obtained CdS/TiO_2 was further modified by multi-wall carbon nanotubes (MWCNTs). The as-synthesized MWCNTs/CdS/TiO_2 photocatalytic composites were characterized by scanning electron microscopy, low temperature nitrogen adsorption-desorption (BET surface area) and hydrogen evolution from water photo-splitting. The influence of MWCNTs on the photocatalytic hydrogen evolution performance for CdS/TiO_2 catalysts was investigated using Na_2S-Na_2SO_3 as a sacrificial electron donor under UV-Vis light irradiation. It is found that hydrogen production(14.0 μmol) from water photo-splitting can be enhanced by introducing MWCNTs into CdS/TiO_2 composites, in comparison to CdS/TiO_2 photocatalysts(11.6 μmol). The average hydrogen production rate can be improved by 18% and the highest rate improvement can be up to 21%.%以P25 TiO_2(德国Degussa化学公司)粉末为原料采用溶胶-凝胶法制备了含有不同CdS质量分数的复合光催化剂,利用多壁碳纳米管(MWCNTs)对CdS/TiO_2进行修饰,制备了一系列不同CdS含量的MWCNT's/CdS/TiO_2光催化材料.对所得的光催化剂进行了扫描电镜、低温氮吸附-脱附及光解水制氢活性的表征.研究了MWCNTs对CdS/TiO_2催化剂体系光解水制氢活性的影响.结果表明,MWCNTs的引入均使得光解水产氢量(14.0 μmol)增加,与未加入MWCNTs的复合光化剂产氢量(11.6 μmol)相比,平均产氢率增加了18%,最高可达21%.