▎ 摘　　要

NOVELTY - Method for preparing graphene sponge involves (i) adding reducing agent and silicon source to a graphene oxide aqueous solution in sequence to obtain a mixed solution, where the silicon source is a silicon source that dissolves or hydrolyzes with water to form silanol, (ii) heat preserving the resulting mixed solution at 80-95 degrees C for 4-12 hours to obtain graphene hydrogel, and (iii) placing the obtained graphene hydrogel in an alcohol aqueous solution for dialysis, and freeze-drying to obtain the product. USE - The method is useful for preparing graphene sponge for air purification in a closed environment (all claimed). ADVANTAGE - The graphene sponge is directly baked and reused at high temperature.