Abstract

Photoelectrochemical (PEC) reaction pioneered by Fujishima and Honda has widely emerged as a potential approach to convert solar energy into chemical energy[1]. Various photoelectrode materials have been explored, among which SrTiO₃ (STO) has gained importance since it can decompose H₂O into H₂ and O₂ without applying an external bias potential as its conduction band level is higher than the redox potential for the H₂ evolution[2]. To improve the PEC activities of STO, doping and/or coupling with metal nano-particle has been adopted. It has been shown that coupling with metal nanoparticle like Au/Ag promotes light absorption in the visible spectral region, which is termed as hot electron injection that enhances anodic photocurrent[3]. On the other hand, although it has been demonstrated that Rh-Doping induces P-type nature[4], there have been very few efforts towards enhancing cathodic photocurrent.

© 2015 Japan Society of Applied Physics, Optical Society of America