The invention belongs to the technical field of the preparation of
graphene, and relates to a preparation method of expanded
graphite paper. The method is as below: 1) immersing the
graphite paper into a low-temperature liquid, maintaining for 30 seconds to 5 minutes, and taking out; 2) and then quickly immersing the
graphite paper into a high temperature liquid, and using rapid gas
precipitation and liquid solidification for
rapid expansion of the sheet layer in the graphite paper; and 3) after expansion, taking out the expanded graphite paper, and then washing and
drying to obtain the expanded graphite paper used for electrochemical stripping. Scanning
electron microscopy (SEM) observation shows that the treated expanded graphite paper has obviously changed morphology, surface wrinkles and destroyed
edge structure, so as to provide favorable conditions for infiltration of
electrolyte into the graphite paper in a subsequent electrochemical stripping process. The yield of
graphene is more than 80%, which provides the possibility for the
mass production of
grapheme.