▎ 摘　　要

A highly efficient graphene nanosheet (GNS) production process based on spontaneous electrochemical reactions - (i) spontaneous lithiation reaction through the direct contact between graphite powder and Li metal in an electrolyte due to the high electrochemical potential difference; and (ii) reaction of Li inside the lithiated graphite with water - is reported. This process, with the absence of supplied energies, is oxidation-free, very fast, scalable and produces a high quality GNS (C/O: 17.9 by EA, I-D/I-G: 0.55 by Raman spectroscopy) with a high yield (>95 wt.%). (C) 2015 Elsevier Ltd. All rights reserved.