Innovative strategies to Counteract Jahn-Teller effect in manganese oxide for enhanced zinc-ion battery performance

Due to its high energy density, non-toxic, economical and efficient, manganese oxide stands out as a promising cathode material for employment in aqueous zinc-ion batteries. However, the Jahn-Teller effect of Mn³⁺ and manganese dissolution impose limitations on the widespread application of aqueous zinc-ion batteries during charging and discharging. Herein, the Co doped Mn₂O₃ electrode material is introduced. Co atoms in the low valence state replace Mn in the manganese oxide lattice, which effectively regulates the layer spacing of Mn₂O₃. This modulation maintains the structural stability of the electrode during cycling, prevents structural collapse, and inhibits manganese dissolution and the Jahn-Teller effect. Additionally, Co doping increased oxygen vacancies and improved the conductivity of zinc-ion batteries. The Co-Mn₂O₃ electrode exhibits a high specific capacity of 478 mAh·g⁻¹ at 0.1 A g⁻¹ current density, with 93 % capacity retention 1000 cycles at 1 A g⁻¹ current density. This study delves into the role of Co doping in suppressing the Jahn-Teller effect, offering new insights for improving manganese oxide as an anode material for zinc-ion batteries.