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

Abstract 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.