Molybdenum Disulfide Nanosheets Interconnected Nitrogen-Doped Reduced Graphene Oxide Hydrogel: A High-Performance Heterostructure for Lithium-Ion Batteries

We demonstrate an efficient and large-scale synthesis approach of a novel heterostructure comprised of molybdenum disulfide (MoS2) and nitrogen-doped reduced graphene oxide (n-RGO) hydrogel (MoS2/n-RGO) via two-step hydrothermal process. Due to the strong molybdenum-nitrogen (Mo-N) bond, the n-RGO sheets are well interconnected to the MoS2 sheets and restacking of the two components is minimized. The hybrid possesses an open-pore structure, large surface area, and high nitrogen content. As an anode for lithium-ion batteries, the MoS2/n-RGO manifests a high specific capacity of 1140 mA h g (1) at the current density of 100 mA g (1), which is higher than that of the MoS2/non-doped RGO (MoS2/RGO) counterpart. A remarkable rate capability and excellent electrochemical stability (94% retention after 130 cycles) is also achieved. Furthermore, the MoS2/n-RGO hybrid delivers a maximum energy density of 890 Wh kg (1) with the power density of 130 W kg (1). The superior electrochemical performance can be attributed to the durability and improved charge kinetics of the MoS2/n-RGO heterostructure owing to the nitrogen-doping effect. This study sheds light on the importance of a nitrogen-doped architecture in the creation of novel functional materials that can act as advanced electrodes for lithium-ion batteries. (C) 2016 Elsevier Ltd. All rights reserved.