▎ 摘　　要

Graphite (natural or synthetic) is the primary source for graphene materials preparation by the top down technology. The preparation of synthetic graphite requires temperatures above 2500 degrees C which represents a high energy cost. Herein we demonstrate that graphene materials can be prepared directly from a pregraphitic material using two of the most widely used procedures (chemical route and solvent exfoliation). In this way, extreme graphitization temperatures are avoided. In general terms, the graphene materials obtained from the pregraphitic materials exhibit similar characteristics to those obtained from graphite. These findings represent a breakthrough in the preparation of graphene materials by the top-down technology with clear environmental and economic advantages. (C) 2015 Elsevier Ltd. All rights reserved.