One-step extended strategy for the ionic liquid-assisted synthesis of Ni3S4–MoS2 heterojunction electrodes for supercapacitors

Abstract

A convenient, self-assembly, ionic liquid-assisted method for the preparation of a Ni₃S₄–MoS₂ heterojunction is reported. The Ni₃S₄ support not only provided high conductivity in the heterojunction for MoS₂, but also showed more compatibility with MoS₂, allowing a long cycle life. The capacity of the Ni₃S₄–MoS₂ heterojunction is 985.21 F g⁻¹ at a current density of 1 A g⁻¹, and it can retain 573 F g⁻¹ after 20 000 cycles at a current density of 10 A g⁻¹. The Ni₃S₄–MoS₂//AC (ASC) device demonstrated a high energy density of 58.43 W h kg⁻¹ when the power density reached 385.95 W kg⁻¹, and it can retain an energy density of 18.75 W h kg⁻¹ even at a high power density of 7500 W kg⁻¹, revealing its potential and viability for practical applications. Furthermore, this work provides a novel method to synthesize M_xS_y–MoS₂ (M = Co, Mn, etc.) heterojunction materials in one step. These heterojunction materials could be used in a wide range of fields such as in HER catalysts, Li ion batteries and supercapacitor electrodes.