Rolling flexible double-MXenes TiCT/VCT hybrid films for microsupercapacitors

Two-dimensional (2D) MXenes with slit-shaped ion diffusion channels have been hot candidates for flexible microsupercapacitors (MSCs), while the large-scale manufacturing of MSCs based on MXene-based films remains a challenge. Herein, different MXenes, Ti3C2Tx and V2CTx nanosheets were stacked and rolled into large-area double-MXenes hybrid films. Then, the large-area hybrid films can be efficiently processed into MSCs by the laser-cutting method. Embedding Ti3C2Tx nanosheets between V2CTx layers to impede the self-restacking of V2CTx and expand the interlayer spacing resulted in high capacitance up to 496F g−1 (2.3F cm−2) and good rate performance of the hybrid films. The assembled all-solid-state MSCs delivered a high energy density of 4.9 mWh g−1 at 350 mW g−1 and long cycling life. Moreover, serving as a power source unit, the MSCs can power a piezoresistive sensor to capture the changes in external pressures. The proposed rolling method for fabricating large-area double-MXenes hybrid films and MSCs was also applicable for other MXenes and 2D nanomaterials, which promoted their applications in flexible MSCs and portable electronic devices.