Inkjet-printed flexible V2CTx film electrodes with excellent photoelectric properties and high capacities for energy storage device

Energy storage devices are progressively advancing in the light-weight, flexible, and wearable direction. Ti 3 C 2 T x flexible film electrodes fabricated via a non-contact, cost-effective, high-efficiency, and large-scale inkjet printing technology were capable of satisfying these demands in our previous report. However, other MXenes that can be employed in flexible energy storage devices remain undiscovered. Herein, flexible V 2 CT x film electrodes (with the low formula weight vs Ti 3 C 2 T x film electrodes) with both high capacities and excellent photoelectric properties were first fabricated. The area capacitances of V 2 CT x film electrodes reached 531.3–5787.0 μF⋅cm −2 at 5 mV⋅s −1 , corresponding to the figure of merits (FoMs) of 0.07–0.15. Noteworthy, V 2 CT x film electrode exhibited excellent cyclic stability with the capacitance retention of 83 % after 7,000 consecutive charge–discharge cycles. Furthermore, flexible all solid-state symmetric V 2 CT x supercapacitor was assembled with the area capacitance of 23.4 μF⋅cm −2 at 5 mV⋅s −1 . Inkjet printing technology reaches the combination of excellent photoelectric properties and high capacities of flexible V 2 CT x film electrodes, which provides a new strategy for manufacturing MXene film electrodes, broadening the application prospect of flexible energy storage devices.