Ni₃S₂@MoS₂ core/shell nanorod arrays on Ni foam for high-performance electrochemical energy storage

In this paper, using Ni₃S₂@MoS₂ as an example, we report the successful design and synthesis of a novel hybrid core/shell metal sulfides with a conductive Ni₃S₂ core by a green, scalable and one-step solution strategy. When they are tested as supercapacitor electrodes, the Ni₃S₂@MoS₂ heterostructure exhibits about 2 times the capacitance (848Fg^-1) compared to the pristine Ni₃S₂ sample (425Fg^-1), excellent rate capability (46.6% capacity retention at 20Ag^-1) and outstanding cycling stability (91% retention after 2000 cycles). The enhancement is ascribed to the robust hierarchical core/shell structures which provide an increased reaction area and a close contact of electrolyte with the active material. In addition, a highly conductive 1D core material endows the quick transport of electrons along Ni₃S₂ nanorods to Ni foam. It is prospected that such novel hybrids can offer great potential promise in large-scale energy storage device applications.