Method for preparing graphene foam/epoxy resin composite material with metamaterial properties

The invention relates to a method for preparing a graphene foam/epoxy resin composite material with metamaterial properties. The method comprises the following steps: mixing concentrated sulfuric acid, natural graphite powder, sodium nitrate and potassium permanganate, adding deionized water, dropwise adding hydrogen peroxide, filtering and washing the obtained substance, carrying out vacuum freeze-drying to obtain graphite oxide, dissolving the graphite oxide in deionized water, adding ammonia water, performing dispersing treatment, heating the obtained dispersion to obtain a graphene hydrogel, freeze-drying the graphene hydrogel to obtain graphene foam, and carrying out high-temperature reduction treatment in the presence of a protective gas; uniformly mixing an epoxy resin, an epoxy curing agent and an epoxy diluent; and impregnating the reduced graphene foam in the above obtained mixed solution, and taking out and solidifying the impregnated reduced graphene foam to obtain the graphene foam/epoxy resin co