Heterogeneous interface-boosted zinc storage of H2V3O8 nanowire/Ti3C2Tx MXene composite toward high-rate and long cycle lifespan aqueous zinc-ion batteries

In this study, H2V3O8/MXene composites as cathode for zinc-ion batteries (ZIBs) were synthesized via one-step high-temperature mixing hydrothermal method. H2V3O8 nanowires with high active sites and Ti3C2Tx MXene with high conductivity promoted efficient Zn2+ storage of H2V3O8/MXene electrode. For zinc storage, the H2V3O8/MXene electrode obtained excellent overall performance with high discharge specific capacity (437.3 mAh g−1 after 500 cycles at 3 A g−1), superior fast charge/discharge ability (highest capacity with 420 mAh g−1 at 10 A g−1), and impressive long-term lifespan (323 mAh g−1 over 9000 cycles at 10 A g−1). The combination of 2D MXene nanosheets and H2V3O8 has the synergistic effect of improving electrical conductivity, enhancing pseudocapacitance and alleviating the volume change of H2V3O8 during insertion/deinsertion process, resulting in high rate and long cycle stability electrochemical performance. Density functional theory calculations further reveal that the interfacial electric field within the H2V3O8-MXene interface leads to the exceptional zinc ion diffusion kinetic and superior zinc storage capacity, thereby achieving outstanding electrochemical activity. This work reveals the effect of the interfacial interaction between the highly conductive 2D MXene material and H2V3O8 on the performance of ZIBs, providing a suitable strategy for efficient energy storage of zinc.