▎ 摘　　要

In this paper, we report a simple and fast approach for producing high-quality graphene (HQG) by electrochemical exfoliation and spark plasma sintering (SPS). Via a pressureless sintering at 1500 degrees C for 10 min, the oxygen-containing groups of electrochemically exfoliated graphene can be effectively eliminated and its intrinsic structures and properties are restored. The experimental results show that: 1) the HQG exhibits very low defect density (I-D/I-G = 0.16), extremely high carbon to oxygen (C/O) ratio of 25.3 and good processability in various solvents; 2) When the HQG is applied to fabricate a free-standing graphene paper (G-paper), its conductivity reaches to as high as 38460 Sim; 3) The G-paper without any binders, which is used as supercapacitor electrodes, delivers a specific capacitance of 129.0 Fig at 1 A/g, and retains 97% capacitance even after 1000 cycles. (C) 2016 Elsevier B.V. All rights reserved.