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

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 MxSy-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.