Enhanced visible-light photoelectrochemical activity of TiO2 nanorod arrays decorated by Sb2S3 particles

Single-crystal TiO 2 nanorod arrays (NRAs) were synthesized successfully onto transparent conducting substrates through a facile hydrothermal route for photo-electrochemical (PEC) water-splitting. Further, the ordered TiO 2 NRAs were treated by SbCl 3 solution for preparing a layer of Sb 2 S 3 and enhancing their PEC activity. A series of methods were employed to compare and analyze the differences between the TiO 2 NRA samples with/without Sb 2 S 3 decoration. It was demonstrated that the PEC performance were enhanced significantly after being treated with SbCl 3 aqueous solution (precursor) under a hydrothermal environment. Compared to pure TiO 2 NRAs, the sample that decorated with Sb 2 S 3 showed a more positive flat-band level as well as a higher donor density (i.e. electron density). Thus, it suggested that the enhanced PEC performance after Sb 2 S 3 modification might be attributed to the widening of spectral response as well as the improvement of charge transfer / transport occurring at the solid/liquid interfaces.