Three-Dimensional Hierarchical MoSe<sub>2</sub>/N, F Co-Doped Carbon Heterostructure Assembled by Ultrathin Nanosheets for Advanced Lithium-Ion Batteries
Qinqin Liang, Lixuan Zhang, Man Zhang, Qichang Pan, Yu Li, Chunlei Tan, Fenghua Zheng, Youguo Huang, Hongqiang Wang, Qingyu Li
Abstract
MoSe2 has attracted great interest as an anode material for lithium-ion batteries (LIBs) thanks to its high capacity. Nevertheless, the poor cycle performance caused by the huge volume change during the lithiation/delithiation process seriously limits its practical application in LIBs. Herein, a 3D hierarchical MoSe2/N, F co-doped carbon (MoSe2/NFC) heterostructure is prepared via a simple method. Notably, the N, F co-doped heterostructure can expand the (002) plane of MoSe2, which contributes in facilitating Li+ insertion/extraction. Furthermore, N, F co-doped carbon confined MoSe2 nanosheets to form a 3D hierarchical heterostructure, leading to fast electron/ion transfer, buffering of the volume change, and prevention of the aggregation of MoSe2 nanosheets during the repeated discharge/charge process. Therefore, the MoSe2/NFC composite exhibits good rate performance and ultra-long cycling life when applied in LIBs. A high capacity of 452.9 mAh g–1 is maintained at 5 A g–1, and a high capacity of 598.3 mAh g–1 is obtained after 1000 cycles at 2 A g–1.