▎ 摘　　要

NOVELTY - Graphene-coated particles are formed by sonicating mixture of fly ash, 1-(4-pyridyl)pyridinium chloride hydrochloride (HCl), and ethanol to form fly ash ethanol dispersion, mixing polymer-supported oxidizing agent with fly ash ethanol dispersion to form dispersed mixture, reacting dispersed mixture comprising fly ash, 1-(4-pyridyl)pyridinium chloride HCl, ethanol, and polymer-supported oxidizing agent to form 2nd mixture comprising polymer-coated fly ash, and contacting 2nd mixture, in liquid form, at 120-180 degrees C with gas stream comprising greater than or equal to 0.1 vol.% methane (CH4) and/or greater than or equal to 10 vol.% hydrogen (H2) to form graphene on the fly ash. USE - Formation of graphene-coated particles. ADVANTAGE - The method provides a fast, facile, and/or cost-effective process of preparing high quality graphene, resulting in mono and/or bilayer graphene free of defects, e.g., greater than or equal to 99.999% planar honeycomb units or area having flawless structure, relative to total units or area. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram for a possible mechanism of growth of graphene on the surface of fly ash.