One-step mild synthesis of δ-MnO2/Ti3C2Tx cathode for aqueous zinc-ion batteries

Manganese -based oxides are deemed to be prospective cathode materials for aqueous zinc -ion batteries (ZIBs). Nevertheless, their practical application was hampered by the slow zinc -ion diffusion dynamics and the instability of MnO2 structure. The 8-MnO2/MXene cathodes have been investigated to overcome the inherent defects of 8-MnO2 and significantly improve the performance of ZIBs. However, these 8-MnO2/MXene cathodes suffer from high -temperature, high-pressure, time-consuming or complicated production processes. To address these issues, 8-MnO2/Ti3C2Tx cathode was synthesized by a one-step in -situ growth strategy under mild conditions. The 8-MnO2/Ti3C2Tx cathode can take advantages of the large specific capacity of 8-MnO2 and the high conductivity of Ti3C2Tx nanosheets. Besides, the highly conductive Ti3C2Tx scaffolds efficaciously suppress the irreversible structural damage of 8-MnO2. Therefore, the ZIB assembled with the 8-MnO2/Ti3C2Tx cathode demonstrates significantly improved electrochemical behavior with a large specific capacity of 320.6 mAh g-1 at 0.1 A g-1, excellent rate capability of 153.0 mAh g-1 at 3.0 A g-1, high energy density of 440.0 Wh kg- 1 at 136.6 W kg - 1, and good cyclability with a capacity retention of 70.2 % after 1500 cycles, significantly outperforming the 8-MnO2 cathode. The findings of this study suggest that the 8-MnO2/Ti3C2Tx composite holds promise as a potential cathode for high-performance aqueous ZIBs.