Nitrogen-doped carbon-coated molybdenum disulfide nanosheets for high-performance supercapacitor

•N-doped carbon/MoS2 (NC-MoS2) were prepared by thin-coating of polydopamine followed by a carbonizaiton process.•TEM image revealed N-doped carbon layers on the surface of MoS2 sheets.•NC-MoS2 electrode significantly improved supercapacitor performance compared to the re-stacked MoS2.

Although exfoliated MoS2 sheets have recently demonstrated their great potential for use as electrodes for supercapacitors, they suffer from poor intrinsic electrical conductivity and strong tendency for intersheet aggregation. Here, we develop a synthetic method for preparation of N-doped carbon-coated MoS2 (NC-MoS2) nanosheets composed of coating of polydopamine and a post carbonization process. Construction of carbon layers on the MoS2 surface enables effective prevention of sheet aggregation and provide a rapid pathway for electron transfer. As-prepared NC-MoS2 materials are then characterized by electrochemical measurements to demonstrate the superior performance of the supercapacitor electrodes. The NC-MoS2 electrode exhibits improved electrochemical performance relative to the exfoliated MoS2 sheets, with a high specific capacitance (158 F g−1), high rate capability (83% retention), and good cycling life (89% retention) during 1000 cycles.