Enhanced photocatalytic performance of platinized CdS/TiO2 by optimizing calcination temperature of TiO2 nanotubes

TiO2 nanotubes were prepared by hydrothermal treatment of TiO2 powder in NaOH aqueous solution and then calcined at various temperatures. The post-calcination treated TiO2 nanotubes were decorated with CdS by wetness impregnation and subsequently sulfurization to fabricate CdS/TiO2 composites. The photocatalytic performance of CdS/TiO2 composites toward hydrogen production from water splitting was investigated. The results show that the calcination temperature of TiO2 nanotubes has a significant effect on the photocatalytic performance of CdS/TiO2. With the increase of calcination temperature from 300 to 500 degrees C, the crystallinity of TiO2 nanotubes is increased resulting in the enhanced photocatalytic performance of CdS/TiO2. When the calcination temperature is higher than 500 degrees C, TiO2 nanotubes gradually transform into nanorods and finally completely collapse, which leads to the decrease of photocatalytic performance of CdS/TiO2. The CdS/TiO2 composite with TiO2 nanotubes calcined at 500 degrees C exhibits the highest hydrogen evolution rate, which could be attributed to its 1 D nanotubular structure and good crystallinity. (C) 2014 Elsevier Ltd. All rights reserved