Constructing Mn₃O₄/MnCO₃ Heterojunction Interface to Enhance the Storage Performance of Zn Ions

Usually, the interfacial problem of electrode materials is considered one of the main factors affecting the electrochemical performance. The construction of heterostructures is an important approach to regulating the material interface. In recent years, manganese-based materials based on aqueous zinc-ion batteries have received great attention, but single-phase structures of manganese-based materials have their limitations. In contrast, heterojunction materials incorporate the advantages of two-phase or multiphase structures to realize synergistic effects. This work realized the rapid transport of zinc ions by the construction of heterojunction interfaces. The Mn 3 O 4 /MnCO 3 heterostructure material prepared by the hydrothermal method exhibits excellent electrochemical properties. The specific capacity was 91.3 mAh g –1 after 6000 cycles at a current density of 3 A g –1, and the capacitance contribution was as high as 93.6% at a scan rate of 0.2 mV s –1 . Electrochemical characterization, ex-situ X-ray diffraction (XRD)/X-Ray Photoelectron Spectroscopy (XPS) analyses, and density of states simulations confirm that the Mn 3 O 4 /MnCO 3 heterojunction materials combine the high stability of Mn 3 O 4 with the high capacity of MnCO 3, making it suitable to be used as the cathode material for aqueous zinc-ion batteries.