In-situ growth of γ-Mn2O3 on activated carbon cloth for enhanced bifunctional electrocatalysis of ORR and OER

Abstract

Developing cost-effective and high-performance electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical for advancements in metal-air batteries, proton exchange membrane PEM fuel cells, and water-splitting systems. These systems require highly active and stable electrocatalysts to enhance the ORR and OER performance to increase the device's efficiency. Herein, we report the synthesis of γ-Mn₂O₃ nanoparticles doped onto activated carbon cloth (A-CC) (γ-Mn₂O₃/A-CC) via simple and scalable hydrothermal process followed by annealing. This work investigates the potential of γ-Mn₂O₃/A-CC as a bifunctional electrocatalyst for ORR and OER in alkaline media. In ORR condition, the γ-Mn2O3/A-CC electrocatalyst exhibited half-wave potential (E_1/2) of 0.708 V, while in OER, the electrocatalyst exhibited overpotential of 522 mV at 10 mA cm⁻² and low Tafel slope of 40.6 mV dec⁻¹. The electrochemical performance of the synthesized catalysts is comparable to the state-of-the-art Pt/C and RuO₂/C electrocatalysts. This study provides a comprehensive understanding of the electrocatalytic activity of γ-Mn₂O₃/A-CC, highlighting its potential application in advanced energy conversion devices.