Electrifying energy storage by investigating the electrochemical behavior of CoCr2O4/graphene-oxide nanocomposite as supercapacitor high performance electrode material

Heliyon. 2024 Nov 26;10(23):e40702. doi: 10.1016/j.heliyon.2024.e40702. eCollection 2024 Dec 15.

Abstract

This study reports novel three-step electrochemical fabrication of CoCr2O4/graphene-oxide nanocomposite on glassy carbon electrode including sequential synthesis of graphene-oxide using modified Hummer's method, CoCr2O4 nanoparticles using sol-gel method and the cost-effective co-precipitation technique for nanocomposite formation. The resulting nanocomposite was subjected to comprehensive analytical and morphological analysis. X-ray diffractometry (XRD) confirms nanocomposite formation with reduced average crystallite size value of 26.9 nm whereas SEM indicates spherical grains existence within nanocomposite. Energy-dispersive X-ray spectrometry (EDS) confirms no impurity peak existence whereas Raman spectroscopy clearly indicated D and G band existence at 1345 and 1587 cm-1 respectively. Photoluminescent spectra reveals decreasing trend in band gap value about 3.49 eV. The electrochemical properties of CoCr2O4/graphene-oxide nanocomposite electrode explored, showcasing remarkable capacitance with a surface area of merely 0.068 cm2, 574.8 F/g specific capacitance in alkaline 1M KOH and 488.6 F/g specific capacitance in acidic 0.1M H2SO4 electrolyte. Moreover, synthesized nanocomposite demonstrates remarkable electrochemical stability resulting capacitance retention about 95 % after 100 cycles in 1M KOH electrolyte. GCD analysis reveals impressive power and energy density values of 2489 W/kg and 14.88 Wh/kg respectively. These outstanding properties make the nanocomposite an attractive material for next-generation supercapacitors and energy storage solutions.

Keywords: CoCr2O4/Graphene-oxide: Nanocomposite; Energy storage; Supercapacitor electrode.