Method for preparing graphene porous membrane

Abstract

The invention provides a method for preparing a graphene porous membrane. The method includes the steps that oxidized graphite is added into water, oxidized graphite dispersion liquid is obtained and subjected to ultrasonic dispersion, and an oxidized graphene solution is obtained; a pore forming agent is added into the oxidized graphene solution and evenly dispersed into oxidized graphene, the mixture is subjected to suction filtration and/or dried, and a composite membrane of the oxidized graphene and the pore forming agent is obtained; the composite membrane of the oxidized graphene and the pore forming agent is reduced and washed, and a composite membrane of graphene and the pore forming agent is obtained; the pore forming agent is removed with an organic solvent, and under the moist condition, the product is further treated with the critical point drying method, and the graphene porous membrane is obtained; the pore forming agent is one or more of homopolymer microspheres and copolymer microspheres. The size of pores inside the graphene porous membrane prepared with the method ranges from 100 nm to 1,000 nm, the porosity can be regulated and controlled by regulating the concentration or the size of the pore forming agent, the yield of the graphene porous membrane is high, and an operating device is simple.

Description

technical field [0001] The invention belongs to the technical field of materials, and in particular relates to a preparation method of a graphene porous membrane. Background technique [0002] Graphene is a two-dimensional honeycomb grid structure composed of a single atomic layer of carbon. Its unique atomic structure and electronic structure enable the material to have excellent electrical, thermal and mechanical properties, as well as a large theoretical specific surface area (theoretical calculation). The value is 2600m 2 / g), which is the best choice for a new generation of supercapacitor electrode materials. However, the incomplete reduction degree of graphene and the stacking due to van der Waals forces during the reduction process lead to poor conductivity of the material, and the specific surface area is much lower than the theoretical value, thus affecting the final performance. [0003] In order to further reduce the stacking of graphene and increase the specifi...

AI Technical Summary

Problems solved by technology

This method has obvious disadvantages: first, it consumes a lot of energy and the treatment conditions are harsh; second, the heat treatment process will cause the volume expansion of the porous membrane; Inhomogeneity, this uncontrollable and disordered structure is not conducive to researchers' research and understanding of the storage and transport principles of substances in porous structures

However, the method of preparing graphene porous membrane by organic solvent dissolution combined with critical point drying has not been reported yet.

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