以氧化石墨烯和CdS为原料,在乙醇水溶液中采用CdS光催化还原法制备了CdS/石墨烯复合光催化材料,并用透射电子显微镜(TEM)、X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱、X射线光电子能谱(XPS)和瞬态光电流等技术对复合材料的结构和光电性能进行了表征.可见光照射下(λ≥420nm),研究了该复合材料光催化分解水产氢的性能.结果表明,可见光照射下CdS的光生电子可有效地还原氧化石墨烯,得到CdS与石墨烯之间具有强相互作用力的CdS/石墨烯复合材料.与CdS相比,复合材料中石墨烯作为良好的电子受体和传递介质,可明显加快CdS光牛电子的迁移速率,提高光生载流子的分离效率,从而增强复合材料的光电性能和光催化分解水产氢的活性.
CdS/graphene composite photocatalysts were prepared by photocatalytically reducing graphene oxide with CdS nanoparticles in an aqueous ethanol solution. The structure and photoelectrical properties of the resulted materials were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and transient photocurrent measurements. The photocatalytic activities of the CdS/graphene composites for hydrogen evolution were evaluated under visible light irradiation (λ≥420 nm). The results show that the graphene oxide can be efficiently reduced by the photogenerated electrons of CdS and thus CdS/graphene composite is formed and it shows strong interactions between CdS and graphene. Compared with CdS, the enhanced photocurrent generation and photocatalytic activity toward hydrogen evolution for the CdS/ graphene composite photocatalysts could be attributed to the ability of graphene to capture and transport electrons, and to promote charge separation.