Cost effective production of high quality multilayer graphene in molten Sn bubble column by using CH4 as carbon source

The cost-effective production of high-quality graphene is one of the bottlenecks for wide applications. This article presents a modified Chemical Vapor Deposition (CVD) method to massively produce multilayer graphene (MLG) on gas-bubble surface in a bubble column with the molten Sn, which is utilized as the heat-transfer agent and catalyst. This method is able to provide a 70 ± 10% yield of MLG from CH4 gas at 1250 ℃,and a 0.27 ± 0.04 g/hr production rate while 300 ml molten Sn used. The produced MLG has around 15 layers with a crumpled structure. It exhibits excellent quality with few structure defects with superior electrical conductivity of ∼2.5 × 105 Sm−1. Furthermore, the polyurethane (PU)/MLG composite produced by the proposed method shows remarkable electromagnetic interference shielding effectiveness (EMI SE), which reaches 55 dB (1 mm thick) with a 3 wt% MLG content, and it has an electrical conductivity of 256.4 Sm−1. It can be concluded that the proposed method has great potential for the industrial cost-effective production of high-quality graphene sheets.