MXene-driven in situ construction of hollow core-shelled Co3V2O8@Ti3C2Tx nanospheres for high-performance all-solid-state asymmetric supercapacitors

Ti3C2Tx MXene-wrapped hollow Co3V2O8 nanospheres were simply prepared by using the pre-prepared Ti3C2Tx nanoflakes as the nucleation site and precursor to promote the uniform growth of hollow Co3V2O8 nanospheres as well as to achieve in situ encapsulation. Profiting from the specific interface coupling and hollow architecture, the unique core-shelled Co3V2O8@Ti3C2Tx presented outstanding capacitive performances in terms of large specific capacitance, fine rate capability, and long-term cycle life. In particular, its capacitance as high as 94.5% could be maintained upon 10 000 cycles even at a high current density of 80 mA cm(-2) (similar to 10 A g(-1)). The as-fabricated solid-state asymmetric supercapacitor assembled by Co3V2O8@Ti3C2Tx and active carbon could output an energy density of 70.2 mu W h cm(-2) at a power density of 3.3 mW cm(-2) with 87.1% of the initial capacity retained after 10 000 cycles, outperforming many similar electrode materials in previous reports. In view of the remarkable performances and facile preparation, Co3V2O8@Ti3C2Tx holds good prospective application potential as a promising cathode candidate for supercapacitors.

Automated summary

In this study, MXene-wrapped hollow Co3V2O8 nanospheres were used as electrode materials for supercapacitors, exhibiting excellent performance and reliable cycle life. The capacitance reached as high as 94.5%, with 87.1% of the initial capacity retained after 10,000 cycles. The solid-state asymmetric supercapacitor showed a high energy density and maintained a high capacity retention rate after long cycle life.