Self-assembled MoO3@α-MnO2 heterostructure as a cycling-stable cathode for aqueous zinc-ion batteries

The practical application of manganese-based cathode materials in aqueous zinc-ion batteries (AZIBs) is hindered by their intrinsically low electrical conductivity and inadequate cycling stability. In this work, a MoO 3 @α-MnO 2 heterostructure was engineered through a self-assembly strategy, and its electrochemical performance as an AZIB cathode was systematically evaluated. The designed heterostructure synergistically integrates the beneficial properties of both phases, thereby simultaneously improving electronic conductivity and structural robustness. One-dimensional (1D) MoO 3 nanoribbons function not only as a structural template and mechanical support but also as a morphology-directing template, effectively optimizing the electronic interaction at the heterointerface and refining the particle size of α-MnO 2 , while their mechanically rigid framework alleviates cathode volume expansion during cycling. Furthermore, strong interfacial electronic interaction and charge redistribution at the heterointerface promote Zn 2+ diffusion kinetics and accelerate redox reaction rates. When employed as a cathode, the MoO 3 @α-MnO 2 composite delivers a high discharge specific capacity of 290.55 mAh g −1 at 0.2 A g −1 and retains 209.71 mAh g −1 after 150 cycles, demonstrating superior cycling stability. Excellent capacity recovery is also observed in rate capability tests, highlighting its reversible electrochemical behavior. Density functional theory (DFT) calculations further corroborate the enhanced electrochemical performance of the heterostructure, while in-situ electrochemical impedance spectroscopy (EIS), along with ex-situ XRD and XPS analyses, elucidate the dynamic structural evolution and underlying charge storage mechanism. This study presents a promising strategy for designing high-performance manganese-based cathodes for advanced AZIBs.