A novel in situ synthesis of TiO2/CdS heterojunction for improving photoelectrochemical water splitting

We report a novel hydrothermal in situ synthesis route for the CdS-sensitized TiO₂ nanorod array films and their photoelectrochemical (PEC) performance are investigated in this paper. Although heterojunctions have been well recognized for enhancing the PEC performance of TiO₂ nanostructures, the specific synthesis methodology of high production quality, low preparation cost, and high controllability over the heterojunction structures is still a hot and open topic. In this work, controllable nanoscale TiO₂/CdS heterojunctions have been successfully realized through hydrothermal synthesis. The absorption spectrum is shown to be broadened from ~350 nm to ~570 nm, and the photocurrent density increases from 0.35 to 2.03 mA/cm², corresponding to photo-conversion efficiency of ~0.88%. The method is considered as an efficient and facile choice in the fabrication of TiO₂-based PEC hydrogen production functional materials.