Rational design of oxygen-vacancy-rich MnO nanoparticles anchored on meteorite crater-like carbon skeleton for high-performance aqueous zinc-ion battery cathodes

Aqueous zinc ion batteries (AZIBs) have garnered significant attention as promising candidates for large-scale energy storage systems, owing to their high energy density, cost-effectiveness, inherent safety, and environmental sustainability. In this study, we introduce a novel composite material, oxygen-deficient manganese oxide integrated with a meteorite crater-like carbon skeleton (Ov-MnO/mC), synthesized via a unique micro-explosion reaction. This innovative synthesis method not only generates a distinctive meteorite crater-like carbon framework but also introduces oxygen vacancies into the MnO structure. When employed as a cathode in AZIBs, the Ov-MnO/mC composite demonstrates remarkable electrochemical performance without the addition of manganese salts to the electrolyte. In particular, at a current density of 0.2 A g−1, the cathode achieves a high specific capacity of 282.6 mAh g−1 and maintains a capacity of 122.0 mAh g−1 even at a high rate of 5 A g−1. Moreover, the cathode exhibits excellent cycling stability, retaining 198.9 mAh g−1 after 80 cycles at 0.2 A g−1 and 63.2 mAh g−1 after 920 cycles at 1 A g−1. The underlying energy storage mechanism is thoroughly investigated using in situ Raman spectroscopy and ex situ XRD analysis, providing valuable insights into the structural evolution of the composite during charge–discharge processes. This research not only advances the development of high-performance manganese oxide-based cathodes but also presents a scalable and practical approach for designing efficient energy storage materials.