Superhigh capacity and rate capability of high-level nitrogen-doped graphene sheets as anode materials for lithium-ion batteries

• Published in: Electrochimica acta 2013-02, Vol.90, p.492-497
• Main Authors: Cai, Dandan, Wang, Suqing, Lian, Peichao, Zhu, Xuefeng, Li, Dongdong, Yang, Weishen, Wang, Haihui
• Format: Article
• Language: English
• Subjects: Annealing; Anode material; Anodes; Density; Graphene; Graphene sheets; Lithium batteries; Lithium-ion batteries; Melamine; Nitrogen atoms; Nitrogen-doped; Two dimensional
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2012.11.105

► N-doped graphene was synthesized by annealing the pristine graphene and melamine. ► The atomic percentage of nitrogen in the sample is as high as 7.04at.%. ► The material shows a good cycle performance and excellent rate capability. A new facile approach is proposed to synthesize nitrogen-doped graphene sheets with the nitrogen-doping level as high as 7.04at.% by thermal annealing pristine graphene sheets and low-cost industrial material melamine. The high-level nitrogen-doped graphene sheets exhibit a superhigh initial reversible capacity of 1123mAhg−1 at a current density of 50mAg−1. More significantly, even at an extremely high current density of 20Ag−1, highly stable capacity of about 241mAhg−1 could still be obtained. Such an electrochemical performance is superior to those previously reported nitrogen-doped graphene sheets. The excellent electrochemical performance can be attributed to the two-dimensional structure, disordered surface morphology, high nitrogen-doping level, and the existence of pyridinic nitrogen atoms. The results indicate that the high-level nitrogen-doped graphene sheets could be a promising anode material for high-performance lithium-ion batteries.