Electrochemical Studies of SrTiO3/Reduced Graphene Oxide Composite for High‐Power Energy Storage and Oxygen Evolution Reaction Applications

Strontium titanium perovskite oxide (SrTiO 3 , STO) has emerged as a promising material for energy applications, but its insulating nature limits its performance. Herein, a hierarchical structure of STO particles (600–700 nm) anchored onto reduced graphene oxide (rGO) is developed and their dual functionality in energy storage and water‐splitting applications is evaluated. The STO–rGO composites exhibit enhanced high‐power electrochemical performance in aqueous electrolytes, driven by their large electrochemical surface area and nondiffusion‐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 demonstrate superior oxygen evolution reaction activity, with a low overpotential of 303 mV, high mass activity, and an improved turnover frequency compared to pristine STO, with better long‐term cycling stability, retaining performance after a 24 h 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 rGO.