Mn3O4/Mn2O3 Heterostructure Composite Anchored on NGF as Cathode for Aqueous Zinc-Ion Batteries: Synergistic Effects and Zn2+ Storage Performance
摘要
As a potential cathode material for aqueous zinc-ion batteries (AZIBs), Mn3O4 attracts extensive attention for its high electrochemical activity and theoretical specific capacity. However, its electrochemical performance is limited by issues, such as insufficient intrinsic conductivity, Mn2+ dissolution, irreversible phase transitions, and sluggish reaction kinetics. To address these bottlenecks, in this paper, a high-efficiency energy storage material composed of Mn3O4/Mn2O3 heterostructures and natural graphite flakes (NGF) (denoted as Mn3O4/Mn2O3@NGF) was precisely prepared via a simple spray-drying–calcination method by regulating the temperature. This material leverages the structural stability of Mn2O3 to compensate for the inherent drawback of Mn3O4 to crystal structure collapse. Meanwhile, the hetero-interface formed between them acts synergistically to suppress irreversible phase transformations during electrochemical reactions. Additionally, NGF not only enhances electrical conductivity but also suppresses Mn dissolution via an ion confinement effect. This unique design endows the material with excellent electrochemical performance, as this material delivers a maximum capacity exceeding 200 mAh g-1 at a current density of 1000 mA g−1, while at a high current density of 5000 mA g−1, it maintains 84% of its initial specific capacity (81.7 mAh g−1) after 1600 cycles. This work provides valuable insights for the development of high-performance cathode materials for AZIBs.