Preparation of Few-Layer Porous Graphene by a Soft Mechanical Method with a Short Rolling Transfer Process

Few-layer porous graphene is a promising material for a variety of fields. However, the synthesis of few-layer porous graphene is a great challenge. Here we report a feasible green path to produce few-layer porous graphene, which was exfoliated from high-pressure graphite balls onto microspheres with rough surfaces by a mild rolling transfer process. Ordinary ball milling equipment was adopted for the low-speed (100 rpm) ball-microsphere rolling transfer process. The rolling time (<10 min) was controlled to obtain porous graphene instead of graphene. The porous graphene on the exfoliating microspheres was then easily dispersed in solution by bath sonication. The product contains very few impure functional groups. The hole size and layer distribution of the few-layer porous graphene have been demonstrated to be 2.37±1.17 nm and 2.4±0.7 layers, respectively, and can be adjusted by redesigning the surface of the microspheres.