Construction of morphology-controllable NiS/Ni3S4 hybrid nanosheets for all-solid-state asymmetric supercapacitors†

Abstract

In this work, a novel 3D NiS/Ni₃S₄ architecture was successfully prepared on carbon cloth (CC) through a typical hydrothermal method followed by an annealing process, which led to multiscale and multicomponent 3D structures, resulting in three-dimensional rod-like stacking with a large surface area, abundant ion-mobility pathways and high electrical conductivity. In a three-electrode setup, the electrode displayed an excellent capacitance of 1191.93 F g⁻¹ at 1 A g⁻¹ and retained good rate performance and long cycling stability with 78.25% retention after 10 000 cycles. An all-solid-state asymmetric device (NiS/Ni₃S₄-2//AC) was fabricated with the optimal NiS/Ni₃S₄-2 electrode and AC electrode, which could deliver a high energy density of 43.43 W h kg⁻¹ at a power density of 900 W kg⁻¹ and a maximum power density of 9086.53 W kg⁻¹ with an admirable operating voltage window of 1.8 V and a satisfactory cycling performance of 78.05% after continuous 10 000 cycles, indicating its potential for real-world application.