Enhanced photoelectrocatalytic activity of IrO2-decorated nano-cuboidal SrTiO3 particles

https://doi.org/10.1016/j.apmt.2025.102654 

Abstract

The formation of a heterojunction by loading a co-catalyst onto a catalyst is one of the methods for improving catalytic efficiency. In this study, IrO2-decorated SrTiO3 (IrO2/SrTiO3) nanocatalysts were successfully prepared by loading IrO2 as a co-catalyst via impregnation method onto the surface of SrTiO3 nanoparticles synthesized via a single-step hydrothermal method. Small crystalline IrO2 particles, <5 nm in size, were identified on the surface of the cuboidal SrTiO3 nanoparticles surrounded by the {100} planes of the perovskite structure. The (photo)electrocatalytic activity of the as-prepared IrO2/SrTiO3 catalysts for photoelectrochemical water oxidation was investigated using linear sweep voltammetry and electrochemical impedance spectroscopy. This study demonstrates that IrO2 particles decorated on the (001) surface of SrTiO3 function effectively as co-catalysts for the oxygen evolution reaction. To determine effective photoelectrodes, this study attempts to investigate the common catalytic characteristics of semiconductor systems (SrTiO3 and IrO2/SrTiO3). The catalytic properties of IrO2/SrTiO3 catalysts allow for more effective solar-to-hydrogen conversion on semiconductor photoelectrodes.