V2CTx MXene based zinc ion hybrid micro-susupercapacitor for flexible wearable electronics

TEM, XRD, XPS and DFT have been employed to investigate energy storage mechanism of FZIHM. • FZIHM demonstrates wide window voltage and good flexibility. • This work may pave the way for further advance high performance zinc-ion hybrid supercapacitors. Aqueous zinc ion hybrid micro-supercapacitor is considered for emerging cutting-edge candidate for micro-energy storage technologies due to their inimitable advantages of low-cost materials, high safety, high abundance and environmental friendliness. The selection of electrode materials and the matching of positive and negative electrodes are of vital importance for enhancing the electrochemical performance of flexible zinc ion hybrid micro-supercapacitor (FZIHM) using V 2 CT x MXene as anode, MoO 3 as cathode, demonstrating an areal capacitance of 108.26 mF cm −2 , along with about 90% capacitance retention even after 5000 loops test. And it also exhibits excellent flexibility with 83.7% capacitance retention even after 1000 bending cycles. The transmission electron microscopy (TEM), X-ray diffractometer, X ray photoelectron spectroscopy (XPS) and theoretical calculation demonstrates that zinc ions entered the interlayer of the V 2 CT x anode during the charging process, resulting in an increase in the d-spacing. During the discharging process, zinc ions were released from the d-spacing of the V 2 CT x anode, and the d-spacing returned to its original position. This work using V 2 CT x MXene as anode material for zinc ion hybrid micro-supercapacitors may pave the way for further advance high-performance zinc-ion hybrid supercapacitors.