Direct growth of porous vanadium nitride on carbon cloth with commercial-level mass loading for solid-state supercapacitors

Mass production of wearable devices with effective three-dimensional (3D) structure is a vital prerequisite for practical energy storage. Vanadium nitride (VN) has been identified as a promising supercapacitor electrode due to its wide negative potential working window, high specific capacitance and outstanding electrical conductivity, Herein, porous VN is grown on carbon cloth (CC) by a dip-coating and nitridation method. Such a VN/CC electrode provides effective 3D structure is beneficial for high mass loading (up to 28.3 mg cm(-2)) with high specific capacitance. Consequently, the as-prepared VN/CC electrode can achieve high areal capacitance of 3.34 F cm(-2) at 5 mA cm(-2). As a result, the flexible symmetric supercapacitor shows robust cycling stability (96% retention over 10,000 cycles) with PVA/KOH gel electrolyte. In addition, high energy/power density (0.341 mWh cm-2 at 1.92 mW cm(-2)) and excellent cycling performance (87% retention over 8000 cycles) are achieved in the assembled solid-state asymmetric supercapacitor cell with Zn-Ni-Co ternary oxides (ZNCO)/NF cathode and VN/CC anode. The results provide a simple route to prepare high mass loading porous VN-based electrodes with outstanding areal capacitance. It is believed that this strategy will favor the development of other transition metal nitride electrodes for commercial use in the future.

Automated summary

Porous vanadium nitride is grown on carbon cloth using a dip-coating and nitridation method. The resulting VN/CC electrode with effective 3D structure allows for high mass loading and high specific capacitance, making it a promising material for practical energy storage.