Construction of Nitrogen-Doped Carbon-Coated MoSe2 Microspheres with Enhanced Performance for Lithium Storage.

Exploring advanced anode materials with highly reversible capacity have gained great interests for large-scale lithium storage. A facile two-step method is developed to synthesize nitrogen-doped carbon coated MoSe2 microspheres via hydrothermal plus thermal polymerization. The MoSe2 microspheres composed of interconnected nanoflakes are homogeneously coated by a thin nitrogen-doped carbon (N-C) layer. As an anode for lithium ion batteries, the MoSe2 /N-C composite shows better reversibility, smaller polarization, and higher electrochemical reactivity as compared to the unmodified MoSe2 microspheres. The MoSe2 /N-C electrode delivers a high specific capacity of 698 mAh g-1 after 100 cycles at a current density of 100 mA g-1 and good high rate performance (471 mAh g-1 at a high current density of 2000 mA g-1 ). The improved electrochemical performance is attributed to the conductive N-C coating and hierarchical microsphere structure with fast ion/electron transfer characteristics.