TiO_2纳米薄膜厚度对CdS纳米柱阵列光电化学性能和稳定性的影响

Effect of TiO_2 Nano-Film Thickness on the Photoelectrochemical Performance and Stability of CdS Nanorod Arrays

利用水热合成法在导电玻璃表面上原位生长CdS纳米柱阵列(CdSNRA),然后通过浸渍提拉法在其表面涂覆TiO_2纳米薄膜,制备CdSNRA@TiO_2异质结复合结构材料。利用扫描电镜、X射线衍射、紫外可见光吸收、拉曼光谱等手段对其形貌和结构进行表征。进一步考察了TiO_2薄膜厚度对CdSNRA@TiO_2复合结构光电极的光电化学性能的影响。结果表明,覆盖50 nm厚TiO_2层的CdSNRA复合结构光电极在可见光下具有更好的光电性能和稳定性,这归因于CdSNRA核和TiO_2壳之间光生电子和空穴的有效分离。

CdS nanorod arrays(CdSNRA)were grown on fluorine-doped tin oxide glass substrates via a hydrothermal process,and TiO2 layers with different thicknesses were coated on CdS nanorods surface via dip-coating under mild conditions.The morphology and structure of CdSNRA@TiO2 were characterized by field-emission scanning electron microscopy,X-ray diffraction,Raman spectroscopy and ultraviolet-visible spectroscopy.Effect of TiO2 nano-film thickness on the photoelectrochemical performance and stability of CdSNRA@TiO2 was studied,results showed that the best performance was obtained with thickness of 50 nm.The improved photoactivity was ascribed to the efficient separation of photogenerated electrons and holes between CdS cores and TiO2 shells.