In-situ oriented oxygen-defect-rich Mn–N–O via nitridation and electrochemical oxidation based on industrial-scale Mn₂O₃ to achieve high-performance aqueous zinc ion battery

As a general problem in the field of batteries, materials produced on a large industrial scale usually possess unsatisfactory electrochemical performances. Among them, manganese-based aqueous rechargeable zinc-ion batteries (ARZBs) have been emerging as promising large-scale energy storage systems owing to their high energy densities, low manufacturing cost and intrinsic high safety. However, the direct application of industrial-scale Mn₂O₃ (MO) cathode exhibits poor electrochemical performance especially at high current rates. Herein, a highly reversible Mn-based cathode is developed from the industrial-scale MO by nitridation and following electrochemical oxidation, which triples the ion diffusion rate and greatly promotes the charge transfer. Notably, the cathode delivers a capacity of 161 mAh g⁻¹ at a high current density of 10 A g⁻¹, nearly-three times the capacity of pristine MO (60 mAh g⁻¹). Impressive specific capacity (243.4 mAh g⁻¹) is obtained without Mn²⁺ additive added in the electrolyte, much superior to the pristine MO (124.5 mAh g⁻¹), suggesting its enhanced reaction kinetics and structural stability. In addition, it possesses an outstanding energy output of 368.4 Wh kg⁻¹ at 387.8 W kg⁻¹, which exceeds many of reported cathodes in ARZBs, providing new opportunities for the large-scale application of high-performance and low-cost ARZBs.