Abstract

Photoelectrochemical (PEC) reaction pioneered by Fu-jishima and Honda wherein a semiconductor photocatalyst is used for converting solar energy into chemical energy has been widely regarded as the means to sustainable energy.^1-3 Over the years it has been established that an efficient semiconductor photocatalyst requires suitable band gap for harvesting the entire solar energy and proper band edge potential for redox reaction to be feasible.[4] Among the various semiconductor photocatalysts, SrTiO₃(STO) has gained a lot of attention since its band edge positions are feasible for redox reactions.[5,6] But its visible light activity is limited since its band edge positions lies in the UV region. To enhance the visible light absorption of STO there has been a lot of widely investigated techniques such as doping an additional element,[7] utilization of hot electrons[8] which are directly injected into the conduction band (CB) of the semiconductor over the Schottky barrier with the assistance of the surface plasmon resonance (SPR) and there exist a few theoretical studies which suggest the structural defect of the STO particularly Ti vacancies and Sr vacancies can also lead to the visible activity in STO.[9]

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