Production of functionalized graphitic carbon materials via solvent-free mechanochemical method for supercapacitors and water treatment

Abstract

A facile and solvent-free mechanochemical method was developed here for the production of large-surface-area functional graphitized carbon materials (GCMs) with sp-hybridized carbon atoms, rich porosity, interlayered architecture by ball milling graphite and CaC2 at room temperature. The resultant GCM can be used as a supercapacitor electrode with capacitance of 238.4 F·g−1 at 0.2 A·g−1 in aqueous KOH solution and an excellent sorbent for heavy metal removal with adsorption of 463 and 1700 mg-Hg·g−1, respectively, at Ce = 9.2 and 230 μg. g−1. Its high capacitance and exceptional adsorbance may be ascribed to the well-developed pore volume (0.55 cm3·g−1), high specific area (~597 m2·g−1), ample alkyne groups, Lewis soft basicity of alkynyl groups and graphite nanosheets, as well as their synergistic interaction within confined space. The sp-hybrid carbon atoms are derived from the alkynyl carbon in calcium carbide, which endows GCM unique porosity and electron/ion transport properties. In view of its excellent electrochemical performance and high adsorption capacities for Hg(II), GCM is of potential application in energy storage and water treatment.