Ni3S2/rGO nanoparticles ensemble by an in-situ microwave irradiation route for supercapacitors

Ni3S2/rGO (reduced graphene oxide) nanoparticles ensemble has been synthesized on the nickel foam as the supercapacitor electrode material by a facile microwave irradiation route. The resultant Ni3S2/rGO electrode exhibits superior capacitive performance, which is severalfold that of the bare Ni3S2. Especially, the Ni3S2/rGO electrode with 20 mg GO precursor (Ni3S2-20) shows highest areal and mass specific capacitances of 1.96 F cm−2 and 1192 F g−1 among all the studied samples, respectively, at the current density of 2 mA cm−2, and the capacitance can be retained to 95.4% after 10,000 cycles at the current density of 10 mA cm−2. A supercapacitor device fabricated by the Ni3S2-20 as both cathode and anode delivers a wide potential window in the range of 0–1.62 V, high areal and mass specific capacitances of 553.2 mF cm−2 and 179.6 F g−1 at the current density of 2 mA cm−2, respectively, together with a high energy density of 67.9 Wh kg−1 at the power density of 535.7 W kg−1. The design of fast and facile synthesis strategy can offer a new insight into developing novel composite electrodes composed of carbon-based materials and pseudocapacitor materials for emerging energy storage applications.