Manganese-based cathodes for aqueous zinc-ion batteries: Mechanistic insights and rational design strategies

Aqueous zinc-ion batteries (AZIBs) are promising for large-scale energy storage owing to their advantages of high theoretical capacity, low cost, and high safety. Manganese-based materials, characterized by rich reserves, low cost, multiple valence states, and relatively high operating potential, represent a very promising cathode material for AZIBs. This article reviews the latest advances in manganese-based cathode materials for AZIBs from a mechanistic perspective, elucidating the evolution of energy storage mechanisms. Representative manganese-based materials, including MnO₂, Mn₂O₃, Mn₃O₄, ZnMn₂O₄, and manganese composite with other materials, are discussed in terms of their structural characteristics, dominant reaction pathways, and electrochemical behaviors. To address challenges of manganese dissolution, structural instability, and poor conductivity, key modification strategies (elemental doping, surface coating, structural design, and electrolyte optimization) are systematically reviewed, with a focus on their ability to enhance cycling stability and rate performance. Finally, this review outlines future research directions of manganese-based materials as AZIBs cathodes, providing a reference for developing high-performance AZIBs.