Manipulating Oxygen Vacancy in SrTiO<sub>3</sub> Nanoparticles to Achieve Enhanced Photoelectrochemical Performance in Water Splitting
Xiaoli Ran, Yang Bai, Hao Zeng, Junhao Zhang, Haitao Fu, Xizhong An, Xiaohong Yang
Abstract
Introducing oxygen vacancies into perovskite-type SrTiO 3 nanoparticles usually takes dual or multiple steps, which are not conducive to subsequent modification and application. Herein, a facile nonstoichiometric method is applied to synthesize a series of oxygen vacancy (V O )-doped SrTiO 3 (Sr 1– X TiO 3 –δ ) as a photoanode material in photoelectrochemical (PEC) water-splitting reactions. Experimental results reveal a nonlinear relationship between the PEC performance and V O concentration in SrTiO 3 nanoparticles. Sr 1– X TiO 3 –δ doped with an appropriate amount of V O can significantly enhance its light response and electrocatalytic activity. The optimal Sr 0.95 TiO 3 –δ demonstrated the best PEC activity with an incident photon-to-current conversion efficiency of 3.144 times higher than that of pristine SrTiO 3 . Enhanced PEC activity is attributed to superior light absorption and retarded photogenerated charge carrier recombination. This work systematically reveals the role of oxygen vacancies in SrTiO 3 nanoparticles for achieving enhanced PEC performance in water splitting, which may offer inspiration for defect engineering of perovskite oxides.