Construction of MnO2–Mn3O4 heterostructures to facilitate high-performance aqueous magnesium ion energy storage

Abstract

MnO₂–Mn₃O₄ heterostructure materials are applied in aqueous magnesium ion energy storage for the first time. The heterostructure yields an exceptionally high pseudocapacitance contribution, resulting in a specific capacitance of 313.5 F g⁻¹ at 1 A g⁻¹, which contrasts with that of MnO₂ (108.8 F g⁻¹) and Mn₃O₄ (123.5 F g⁻¹). Additionally, it shows potential for practical applications as a cathode for magnesium ion hybrid supercapacitors (MHS).