Electrochemical Studies of SrTiO3/Reduced Graphene Oxide Composite For High-Power Energy Storage and Oxygen Evolution Reaction Applications.

Abstract

Strontium titanium perovskite oxide (SrTiO3, STO) has emerged as a promising material for energy applications, but its insulating nature limits its performance. In this study, we developed a hierarchical structure of STO particles (600-700 nm) anchored onto reduced graphene oxide (rGO) and evaluated their dual functionality in energy storage and water-splitting applications. The STO-rGO composites exhibited enhanced high-power electrochemical performance in aqueous electrolytes, driven by their large electrochemical surface area and non-diffusion-controlled charge storage process. Furthermore, symmetric supercapacitors and asymmetric supercapacitors fabricated with STO-rGO composites demonstrate excellent electrochemical performance, achieving stable cycling stability with 90% and 95% capacity retention after 10,000 cycles, respectively, highlighting the potential of STO-rGO composites as high-power electrodes. Additionally, STO-rGO composites demonstrated superior oxygen evolution reaction (OER) activity, with a low overpotential of 303 mV, high mass activity, and an improved turnover frequency (TOF) compared to pristine STO, with better long-term cycling stability, retaining performance after a 24-hour chronopotentiometry test at a current density of 10 mA cm⁻².  This work demonstrates the dual functionality of strontium-based perovskite materials for energy storage and water-splitting applications, with significantly enhanced performance achieved through the incorporation of reduced graphene oxide.