▎ 摘　　要

NOVELTY - The low-cost large-scale preparation method of graphene involves preparing divalent metal cation chloride or nitrate salt aqueous solution (A) and trivalent metal cation chloride or nitrate salt aqueous solution (B), dispersing organic anion in solvent (D) to obtain solution (C), stirring the solution (C), dripping aqueous solution (A) and aqueous solution (B) in solution (C), adjusting the pH value to 6-12 using 30 %mass sodium hydroxide solution to obtain sample, aging the sample, washing aged sample with deionized water and then filtering. USE - The method is useful for preparing graphene (claimed). ADVANTAGE - The method enables environmentally-friendly, economical and large-scale preparation of graphene with high degree of bulkiness, efficiency and purity under mild reaction conditions. DETAILED DESCRIPTION - The low-cost, large-scale preparation method of graphene involves preparing divalent metal cation chloride or nitrate salt aqueous solution (A) and trivalent metal cation chloride or nitrate salt aqueous solution (B), sufficiently dispersing organic anion in solvent (D) to obtain solution (C), stirring the solution (C), dripping aqueous solution (A) and aqueous solution (B) in solution (C), adjusting the pH value to 6-12 using 30 %mass sodium hydroxide solution to obtain sample, aging the sample at 50-90 degrees C for 10-18 hours, washing aged sample with deionized water, then filtering to obtain filtrate having pH value of 7-8, vacuum drying the filtrate at 50-100 degrees C for 3-8 hours to obtain organic anion intercalated hydrotalcite, placing organic anion intercalated hydrotalcite in a tube furnace, then calcining under the protection of inert gas at 600-1600 degrees C for 1-6 hours and cooling to room temperature to obtain crude product, refluxing the crude product at 60-200 degrees C for 3-12 hours, then adding acid solution and testing using metal reagent to obtain reflux liquid containing intercalated hydrotalcite precursor of divalent and trivalent metal ions, washing the reflux liquid with deionized water, filtering the washed product, ultrasonically dispersing the filtrate in ethanol solution for 1-3 hours to obtain dispersed graphene, and freeze-drying obtained product for 1 day.