Fabrication of highly uniform spherical carbon nanocomposite at ultra-high yield and their evaluation for supercapacitor application

Micron-sized carbon nanocomposites in highly uniform spherical forms were improved for their productivity using the microwave synthesis technique and then they were evaluated as supercapacitor electrodes . A colloidal suspension of graphite (Gr) in dimethylformamide was initially subjected to a high-power sonication before mixing it with a solution of nanodiamonds (ND) in xylene to finally form spherical carbon nanocomposites at a yield of ~ 94%. The produced particles of ND-Gr nanocomposites have a size distribution within the range 0.6–1.2 um. The electrodes formed of this nanocomposite show promising gravimetric and areal capacitance calculations. The obtained values were further improved from 8.3 F/g and 20 F/cm 2 to 25 F/g and 60 F/cm 2 at a current density of 0.3–1 A/g, respectively, with a high cycle stability by adding hydroquinone into H 2 SO 4 electrolyte. This ND-Gr nanocomposite might be a viable component for supercapacitor and other applications. Graphical abstract