Dopamine Self-Polymerization Enables an N-Doped Carbon Coating of Exfoliated MoS2 Nanoflakes for Anodes of Lithium-Ion Batteries

The molybdenum sulfide has a layered structure, similar to graphite, and delivers a good transfer channel for lithium ions as an anode. To enhance the discharge capacity and cycling stability of the molybdenum sulfide, exfoliated MoS 2 nanoflakes with a N-doped carbon coating were prepared by exfoliation of bulk MoS 2 and carbonization of a polydopamine coating. The morphological characteristics show that the carbonized polydopamine was coated on the surface of MoS 2 nanoflakes successfully. Consequently, as-prepared E-MoS 2 @NC delivers a good electrochemical performance and cycling stability as the anode for lithium-ion batteries; the reversible lithium storage capacity was up to 650 mAh g −1 at a current density of 0.2 A g −1 , and the discharge specific capacity was stabilized at 562 mAh g −1 even after 200 cycles at a current density of 0.5 A g −1 . Graphical Exfoliation and carbon coating : The exfoliation and polydopamine coating method are combined to prepare a N-doped carbon coating of exfoliated MoS 2 nanoflakes for anodes of lithium-ion batteries. The exfoliation treatment reduced the MoS 2 particle size and shortened the Li-ion migration path. The N-doped carbon coating enhanced the conductivity of exfoliated MoS 2 nanoflakes, promoted the lithium ion transport, and enhanced the corresponding electrochemical performance. The discharge specific capacity could be stabilized at 562 mAh g −1 after 200 cycles at a current density of 0.5 A g −1 .