Facile Synthesis of Molybdenum Disulfide Nanosheets/Nitrogen-Doped Porous Carbon Composites for High-Performance Anode Material in Lithium-Ion Batteries

Abstract

A facile strategy to prepare MoS2 nanosheets/nitrogen-doped porous carbon (MoS2/NDPC) composites is designed based on liquid-phase exfoliation (LPE). For preparation of MoS2/NDPC, chitosan (CS) is not only served as a good medium for LPE of MoS2, but also acted as carbon sources for creating NDPC matrix. Through CS-assisted LPE of MoS2, the obtained CS-stabilized MoS2 nanosheets dispersion is further lyophilized into the CS/MoS2 nanosheets foams. By carbonization of CS/MoS2 nanosheets foams, the MoS2/NDPC composites with MoS2 nanosheets embedded in the NDPC are successfully derived. The obtained MoS2/NDPC composites can facilitate fast Li-ion transport and the NDPC enhance the electronic conductivity and retain the structure integrity. Therefore, the MoS2/NDPC composites can be used as high-performance anode material in Lithium-ion batteries, and exhibit outstanding long-life cycling capability at high rates, namely, a specific capacity as large as 1260 mA h g−1 at 0.1 A g−1 and 434 mA h g−1 at 10 A g−1 after 50 cycles. At a current density of 5 A g−1, the MoS2/NDPC composites still show a high discharge capacity of ∼ 496 mA h g−1 after 1000 cycles.