Fabrication of a High-Performance Hybrid Supercapacitor Based on NiCo2S4 Nanoneedles/Biomass Porous Carbon

The three-dimensional activated carbon network with porous structure was prepared by calcining and etching the platanus fluff with the aid of Co­(NO3)·6H2O and KOH. The biomass porous carbon (BPC) derived from platanus fluff exhibited developed meso-macroporous structure and great electrochemical performance (175 F g–1 at 1 A g–1). Herein, the NiCo2S4/BPC was synthesized by a two-step hydrothermal method and utilized as the competitive materials of the supercapacitor electrode. The NiCo2S4/BPC electrode displayed a better specific capacity than that of the pure NiCo2S4 electrode in the three-electrode device. Moreover, the hybrid supercapacitor (HSC) of NiCo2S4/BPC||BPC displayed a high energy density of 38.5 W h kg–1 at 738.1 W kg–1 within a wide voltage range of 0–1.6 V. It is noteworthy that NiCo2S4/BPC||BPC also showed superior cycling stability to NiCo2S4||BPC. Using BPC with a developed porous structure as a conductive substrate not only improves the electrochemical performance of NiCo2S4 but also provides new thoughts for the development of high-performance HSCs.