MoS2 Nanosheets with Conformal Carbon Coating as Stable Anode Materials for Sodium-Ion Batteries

•Carbon coating on MoS2 was achieved by CVD using ethanol vapor as carbon source.•Enhanced conductivity and stabilized nanosheets due to the coating were verified.•Carbon coated MoS2 nanosheets exhibit high rate capability and cycle stability.

MoS2 nanosheets with conformal carbon coating are achieved via a facile, chemical vapor deposition process, employing ethanol vapor as carbon source. The uniform carbon layers are semi-graphitized, which facilitate kinetics for electron and ion transfer, accommodate volume variation of MoS2, and relieve dissolution of polysulfide during repeated discharge/charge cycles. As anode materials for sodium-ion batteries, the optimized carbon coated MoS2 nanosheets show stable reversible capacity of ∼500 mAh g−1 for 100 cycles at 0.1 A g−1, and maintain 351.6 mAh g−1 after 200 cycles even at 1 A g−1. Furthermore, the enhanced electron transfer, and the stabilized structure are verified through electrochemical impedance spectroscopy, cyclic voltammetry, as well as scanning electron microscopy. Our results show that the carbon coating by chemical vapor deposition is efficient and promising to improve the reversible Na+ storage performance of anode materials.

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