Multilayer graphene spheres generated from anthracite and semi-coke as anode materials for lithium-ion batteries

Synthetic graphite, similar to the natural one, has been widely used as anode materials for lithium-ion batteries, but it is still challenging to find a cost-effective and environmentally friendly procedure to graphitize abundant coal based carbonaceous materials. Herein, we describe a scalable graphitization strategy to convert anthracite and semi-coke into open-shell hollow multilayer graphene spheres using nickel as catalyst at relatively low temperature. The as-obtained multilayer graphene spheres show impressive electrochemical performances including high reversible capacity of 389.8 and 401.4 mA h g−1 at 0.1 A g−1 for the graphene spheres generated from anthracite and semi-coke and superior cycling stability as anode materials for lithium-ion batteries. The underneath graphitization mechanisms for anthracite and semi-coke are proposed. The work provides an efficient route for the large-scale production of graphene-based anode materials for lithium-ion batteries from other carbonaceous materials.