Boosting Reversibility and Capacity in Aqueous Zinc-Ion Batteries via Lanthanum-Doped MnO2 Cathodes.

Abstract

Manganese-based aqueous zinc-ion batteries (AZIBs) are regarded as promising candidates for large-scale energy storage owing to their safety, low cost, and environmental sustainability. Nevertheless, their practical deployment is limited by the poor electrical conductivity and structural instability of manganese-based cathodes, particularly the dissolution of active materials during cycling. In this study, lanthanum-doped manganese dioxide (La-doped MnO2) was synthesized through a mechanochemical reaction, followed by annealing to overcome these challenges. The incorporation of lanthanum markedly improves both the electrical conductivity and structural stability of MnO2. Consequently, the La-doped MnO2 cathode delivers enhanced electrochemical performance, achieving a high specific capacity of 288 mA·h·g-1 at 0.1 A·g-1 and excellent cycling stability, with 81% capacity retention at 0.4 A·g-1 after 500 cycles. These results reveal the potential of La-doped MnO2 as a high-performance cathode material for next-generation aqueous ZIBs.