A binary solvent system for improved liquid phase exfoliation of pristine graphene materials

Up to now, the cost-effective mass production of pristine graphene sheets remains a significant challenge. We report a binary solvent system of dimethylformamide and n -butylalcohol that facilitates the high concentration production of unoxidized graphene through liquid-exfoliation assisted with sonication . A stable dispersion with concentration as high as 6.5   mg/ml, was received via this method. The conductivity of a film made from the graphene sheets had a conductivity of 27,000   S/m. The supercapacitor fabricated by graphene exhibits a giant capacitance of 600   F/g and an outstanding long-term stability.