Scalable synthesis of Sm₂O₃/Fe₂O₃ hierarchical oxygen vacancy-based gyroid-inspired morphology: With enhanced electrocatalytic activity for oxygen evolution performance

Non-platinum-based critically and rationally fabricated electrocatalysts show promising efficiency in electrochemical oxygen evolution reaction (OER) due to their reliability and cost-effectiveness. Herein, a hydrothermally designed oxygen-defective Sm₂O₃/Fe₂O₃ composite with gyroid morphology provides superior active sites with high porosity and mass charge transport in a catalytic system. All of the fabricated materials were characterized via different analytical techniques. The Sm₂O₃/Fe₂O₃ hierarchical composite displays an outstanding lower overpotential (272 mV) to attain a current density of 10 mA/cm² and a lower Tafel slope (75 mV/dec) compared to the individual materials Sm₂O₃ and Fe₂O₃ in alkaline media. The remarkable electrocatalytic intrinsic OER performance of oxygen-defective Sm₂O₃/Fe₂O₃ is ascribed to the strong synergistic effect among both materials due to their unique gyroid structure, and such architecture exhibits extraordinary electrical properties due to its porous structure. Hierarchical Sm₂O₃/Fe₂O₃ exhibits marvelous activity and stability at an applied potential (0.7 V) with a slight decrease in current density. All of the extraordinary results acquired from electrochemical activity make Sm₂O₃/Fe₂O₃ a promising electrocatalyst for electrochemical energy generation.