Assembly of Co3S4 nanoporous structure on Ni foam for binder-free high-performance supercapacitor electrode

A facile method was proposed to synthesize a Co 3 S 4 -based binder-free electrode (Co 3 S 4 /Ni foam) in an aqueous solution containing 1-thioglycerol, cobalt nitrate, and sodium thiosulfate at 60 ℃, followed by calcination at 400 ℃. The Co 3 S 4 membrane on Ni foam consists of spherical and elliptical nanoparticles, which were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The electrochemical investigation of the Co 3 S 4 /Ni foam electrode with cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) exhibits high areal capacitance (7.32 F cm −2 at 10 mA cm −2 ) and ultra-long cycling life (capacitance retention of 75% after 5000 charge/discharge cycles). The asymmetric supercapacitor device (ASC) assembled with Co 3 S 4 /Ni foam and activated carbon (AC) as positive and negative electrodes presents excellent electrochemical performances, suggesting the great application prospect of Co 3 S 4 /Ni foam.