▎ 摘　　要

Transformation of carbon nanomaterials to different allotropes is a very promising approach for preparing a variety of carbon nanomaterials. Herein, we present the catalyst and substrate-free synthesis of graphene (G) nanosheets from fullerene (C60) clusters. G nanosheets were formed from an unzipping process of fullerene clusters using a direct pulse current via a pulsed current sintering method, in which carbon atoms were evaporated from fullerenes as a result of generation of locally high temperatures. Fullerene clusters and G nanosheets were analyzed by different characterization tools and it was demonstrated that G can be successfully synthesized using transformation of fullerenes as starting materials without the need for catalyst or substrate.