The invention discloses a preparation method of a
graphene material. The preparation method includes the following steps that (1) after
graphite and
alkali metal are evenly mixed, vacuumizing and heat treatment are carried out, so that
alkali metal intercalation
graphite is obtained; (2) the
alkali metal intercalation
graphite is collected to be added into molten
ionic liquid, after even stirring is conducted, the mixture is placed into an ultrasonic
pulverizer, ultrasonic treatment is performed, and accordingly
graphene suspension liquid is obtained; (3) the
graphene suspension liquid is filtered,
organic solvent for filtering residues is collected for washing and filtering, then, deionized water is used for conducting repeated washing and filtering until an eluate is neutral, filter objects are dried, and hence the graphene material is obtained. The invention further discloses the graphene material obtained through the preparation method. According to the graphene material and the preparation method thereof, the graphite and the alkali
metal are mixed to be subjected to heat treatment first, the alkali
metal intercalation graphite is obtained and then is dispersed into the
ionic liquid, and after ultrasonic treatment is completed, the graphene material which is complete in laminated structure, high in
monolayer rate and good in
dispersity can be obtained; the method is simple, cost is low, efficiency is high, and the graphene material and the preparation method thereof are suitable for industrial production.