▎ 摘　　要

NOVELTY - The method comprises preparing graphene sheets by hydrogen induced exfoliation of graphitic oxide, decorating the iron oxide nanocrystals, preparing graphitic oxide by oxidation of pure graphite, further thermally exfoliating the graphitic oxide at a temperature of 200 degrees C under hydrogen atmosphere to synthesize graphene sheets, treating the resulting hydrogen exfoliated graphene sheets with concentrated nitric acid resulting in the hydrophilic functional groups including carboxyl, carbonyl and alcohol at a surface of graphene sheets, and washing the functionalized graphene sheets. USE - The method is useful for manufacturing iron oxide-graphene nano composite that is useful for the manufacture of electrodes for water purification (claimed). ADVANTAGE - The method is capable of economically manufacturing iron oxide-graphene nano composite with less number of steps. The nanocomposite allows removal of arsenic, sodium, magnesium, calcium and potassium with high desalination efficiency and low energy consumption, and manufactures the electrode with good mechanical strength and performance. DETAILED DESCRIPTION - The method comprises preparing graphene sheets by hydrogen induced exfoliation of graphitic oxide, decorating the iron oxide nanocrystals, preparing graphitic oxide by oxidation of pure graphite, further thermally exfoliating the graphitic oxide at a temperature of 200 degrees C under hydrogen atmosphere to synthesize graphene sheets, treating the resulting hydrogen exfoliated graphene sheets with concentrated nitric acid resulting in the hydrophilic functional groups including carboxyl, carbonyl and alcohol at a surface of graphene sheets, washing the functionalized graphene sheets and then drying, suspending the functionalized graphene in deionized water by ultrasonication, dissolving iron (III) chloride and iron (II) sulfate in de-ionized water in the stoichiometric ratio of 3:2, heating the solution at a temperature of up to 90 degrees C, adding ammonia solution and graphene sheets dispersed solution in a volumetric ratio of 1:5 to the solution, stirring solution at a temperature of 90 degrees C for 30 minutes and then cooling to room temperature to obtain iron oxide-graphene nanocomposite as a black precipitate, and filtering and washing the precipitate to neutral with water.