▎ 摘　　要

Ultrasonication of graphite nanoplatelets for 10 min to 10 h produced multilayer graphene flakes (GFs) with average lateral sizes of 4.5-1.0 mu m and as few as four stacked layers. Raman and X-ray photoelectron spectroscopies of GFs fabricated using a short sonication time (1 h) indicated that their qualities were quite high, probably due to a low level of introduced defects and their presence mainly at the edges of the GFs. Characterization of GFs used as the anodes of lithium ion batteries revealed a large reversible capacity of 597 mAh/g in the first cycle and a good cycle characteristic in the second to tenth cycles. Unlike the reported behaviors of graphene nanosheets and nanoribbons, reversible lithiation and delithiation were governed by intercalation and deintercalation. (C) 2012 Elsevier B.V. All rights reserved.