Mn2O3/Al2O3 cathode material derived from a metal–organic framework with enhanced cycling performance for aqueous zinc-ion batteries

Abstract

Rechargeable aqueous zinc-ion batteries (ZIBs) are considered to be potential candidates for large-scale energy storage due to their high capacity, low cost, high safety and environmental friendliness. A key problem encountered in Mn-based cathodes is the dissolution of Mn²⁺ that causes significant capacity fading. Herein, a novel Mn₂O₃/Al₂O₃ composite material with a microbundle structure was synthesized using a strategy called ‘MOFs as precursors’. Uniform distribution of Mn₂O₃ and Al₂O₃ with a precise controlled Mn/Al molar ratio can be easily realized using this method. After compositing with Al₂O₃, the resulting material shows not only a higher capacity but also a better cycling stability (118.0 mA h g⁻¹ after 1100 cycles at 1500 mA g⁻¹) than the pure Mn₂O₃. Combined with the ICP analysis, it can be deduced that Al₂O₃ can effectively inhibit the dissolution of Mn²⁺ from Mn³⁺ disproportionation. Our result can provide some inspiration for the modification of Mn-based materials and other materials used in zinc ion batteries or other battery systems.