In situ growth of MnO nanoparticles on accordion-like TiCT MXene for advanced aqueous Zn-Ion batteries.

Manganese-based cathodes are competitive candidates for state-of-the-art aqueous zinc-ion batteries (AZIBs) because of their easy preparation method, sufficient nature reserve, and environmental friendliness. However, their poor cycle stability and low rate performance have prevented them from practical applications. In this study, MnO nanoparticles were formed in situ on the surface and between the interlayers of TiCT MXene, which was pretreated by the intercalation of K ions. TiCT MXene not only provides abundant active sites and high conductivity but also hinders the structural damage of MnO during charging and discharging. Benefiting from the well-designed K-TiC@MnO structure, the battery equipped with the K-TiC@MnO cathode achieved a maximum specific capacity of 312 mAh/g at a current density of 0.3 A/g and carried a specific capacity of approximately 120 mAh/g at a current density of 1 A/g, which remained stable for approximately 500 cycles. The performance surpasses that of most reported MnO-based cathodes. This study pioneers a new approach for building better cathode materials for AZIBs.