▎ 摘　　要

NOVELTY - Composite nanomaterial comprises 15-55 pts. wt. graphene oxide nanosheets, 30-50 pts. wt. carbon airgel, 5-10 pts. wt. nano titanium dioxide and 1-3 pts. wt. nano-silver particles, where carbon airgel, nano-titanium dioxide and nano-silver particles are supported on the surface of graphene oxide nanosheets. USE - The composite nanomaterial is useful in air purification, removing formaldehyde and other organic pollutants in the air and inhibiting and killing bacteria (all claimed). ADVANTAGE - The composite nanomaterial: has the functions of adsorption, oxidation purification and sterilization; combination of graphene oxide and carbon aerogel enriches the pore structure and surface functional group properties of the material, not only for formaldehyde, but also for other organic pollutants such as benzene, toluene, ammonia and other organic pollutants. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing composite nanomaterial, comprising (i) dispersing graphite powder into concentrated sulfuric acid in an ice bath at 0°C, adding potassium permanganate under stirring conditions, after fully stirring, raising the temperature to 30-35°C, adding deionized water, adding 30% hydrogen peroxide after fully stirring, centrifuging after fully stirring, using 5% hydrochloric acid solution, deionized water and acetone to repeatedly wash to obtain graphite oxide nanosheets, placing obtained graphite oxide nanosheets in a flask, adding solvent, placing the flask in an ultrasonic cleaning machine for ultrasonication, and removing the solvent to obtain graphene oxide nanosheets, (ii) adding carbon source to the mixed solvent of absolute ethanol/water to form a uniform and stable solution, and adding prepared graphene oxide nanosheets, stirring at room temperature for 1-2 hours to obtain mixed solution, filtering mixed solution, washing, drying, and baking at 400-500°C for 4-12 hours under an inert atmosphere to obtain graphene oxide nanosheet/carbon airgel material, and (iii) dissolving silver nitrate in absolute ethanol to obtain an silver nitrate ethanol solution, adding ethyl acetate, tetrabutyl titanate and glacial acetic acid to it, and stirring for 8-12 minutes to obtain uniformly mixed mixture, then adding the graphene oxide/carbon airgel material into the mixed solution, stirring in the reaction kettle of the polytetrafluoroethylene substrate after stirring for 30-60 minutes, reacting at 120-160°C for 12-24 hours to obtain solid product, washing the solid product, drying and calcining to obtain composite nanomaterial.