Novel core-shell multi-dimensional hybrid nanoarchitectures consisting of Co(OH)2 nanoparticles/Ni3S2 nanosheets grown on SiC nanowire networks for high-performance asymmetric supercapacitors

Abstract

In this paper, a core-shell multi-dimensional nanoarchitecture based on the uniform and well-aligned 0-dimension (0D) Co(OH)2 nanoparticles (NPs)/2-dimension (2D) Ni3S2 nanosheets (NSs) composites grown on 1-dimension (1D) SiC nanowire networks (NNs) skeletons with splendid resistances to oxidation and erosion, good conductivity and large specific surface area is rationally designed and constructed by a simple hydrothermal and electrodeposition route for the first time, which can act as an advanced free-standing electrode for high-performance asymmetric supercapacitor (ASC). The intriguing structural merits make the obtained SiC@Co(OH)2/Ni3S2 hybrid electrode possess the superior electrochemical performances with specific capacitance of 2318 F g−1 (i.e. 2.56 F cm−2) at a current density of 6 mA cm−2 and a prominent rate capability of ∼86% at 20 mA cm−2, and it is superior than that of solitary SiC@Co(OH)2, SiC@Ni3S2 and Co(OH)2/Ni3S2 electrodes. Interestingly, the hybrid electrode can exhibit stable electrochemical performances at wide temperature range of 25–75 °C, even through it was cold down to 25 °C again, its capacitive features is virtually coincident with the initial state. In addition, a hybrid ASC is fabricated with the SiC@Co(OH)2/Ni3S2 as a positive electrode and SiC@Fe2O3 nanoneedle arrays as a negative electrode to achieve high energy density of 81 W h kg−1 at a power density of 1.2 kW kg−1 and delivers amazing cycling stability of 85.1% retention over 5000 cycles. The findings offer an example about the reasonable design of an efficient multi-dimensional nanostructure electrode for ASCs with high energy density, holding great application prospects for future multifunctional electronic devices.