▎ 摘　　要

NOVELTY - Preparation of graphene comprises adding 2.1-21.3 g sodium silicate to 40 mL deionized water; impregnating expanded graphite (EG) with sodium silicate in an aqueous solution for 10-120 minutes; adding deionized water to sodium aluminate and sodium hydroxide to obtain a solution; stirring and slowly dropping the solution to infuse sodium silicate solution at room temperature for 2-12 hours; placing in a reaction kettle; reacting at 80-200 degrees C for 8-24 hours; filtering, washing, and drying the product dispersed in ethanol; and ultrasonic dispersing for 4-16 hours, filtering, and drying. USE - Method for the preparation of graphene (claimed). ADVANTAGE - The method has low raw material cost, is simple and convenient, is environment-friendly, and obtains large and thin graphene sheets. DETAILED DESCRIPTION - Preparation of graphene comprises: (A) adding 2.1-21.3 g sodium silicate to every 40 mL deionized water; (B) impregnating EG with sodium silicate in an aqueous solution for 10-120 minutes; (C) adding 15 mL deionized water to 1.2 g sodium aluminate and 0.3-4.5 g sodium hydroxide to obtain a solution; (D) stirring and slowly dropping the solution to infuse sodium silicate solution, where the mass ratio of EG, sodium silicate, sodium aluminate, and sodium hydroxide is 0.2-1.2: 2.1-21.3: 1.2:0.3-4.5, at room temperature for 2-12 hours; (E) placing in a PTFE substrate of a reaction kettle; (F) controlling the reaction temperature at 80-200 degrees C, and reacting for 8-24 hours; (G) filtering, washing, and drying the product dispersed in ethanol; and (H) ultrasonic dispersing for 4-16 hours with circulating cold water to obtain stable dispersion, filtering, and drying.