Relaxing volume stress and promoting active sites in vertically grown 2D layered mesoporous MoS2(1-x)Se2x/rGO composites with enhanced capability and stability for lithium ion batteries. (1st April 2018)

• Record Type: Journal Article
• Authors: Wang, Shasha; Liu, Baocang; Zhi, Guolei; Gong, Xia; Gao, Zhiqing; Zhang, Jun
• Is Part Of: Electrochimica acta. Volume 268(2018)
• Page Start: 424
• Page End: 434
• Publication Date: 2018-04-01
• Subjects: Mesoporous material -- 2D layered structure -- Transition-metal chalcogenide -- Graphene -- Lithium ion battery; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2018.02.102
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: In this paper, an effective strategy to fabricate mesoporous MoS2(1-x) Se2x composites supported on graphene sheets (meso-MoS2(1-x) Se2x /rGO) for use as anode materials for lithium ion batteries (LIBs) is reported. The meso-MoS2(1-x) Se2x /rGO composites possess a two-dimensional (2D) layered structure with well-defined mesoporosity and the MoS2(1-x) Se2x nanoparticles are perpendicularly grown on graphene sheets. Due to the merits of 2D layered structural configuration and sulfur-selenium coupled effect, the meso-MoS2(1-x) Se2x /rGO composites promise the enhanced electrochemical performance for LIBs. Introduction of Se may widen the spacing of the (002) crystal plane, as a result, rendering them more effective diffusion path for both Li + and e − during the charge and discharge process. More importantly, Se incorporation may further induce the transition of meso-MoS2(1-x) Se2x from 2H phase to more metallic 1 T phase. As such, the meso-MoS1.12 Se0.88 /rGO electrodes exhibit efficient rate capability and good cycling stability with an optimum capacity of 830 mA h g −1 at a current density of 100 mA g −1 for 150 th cycle. The meso-MoS1.12 Se0.88 /rGO electrode still keeps a capacity of 415.3 mA h g −1 even when the current density is 1000 mA g −1 making them promising for potential practical application. The novel synthetic strategy may be applicable to fabricate a large variety of 2D layered chalcogenide electrode materials for LIBs. Graphical abstract: Highlights: Vertically anchored MoS2(1−x) Se2x nanoparticles on conductive graphene is proposed. Incooperation of Se enlarges the (002) interplanar spacing and provides more effective transport channel. Phase transition from 2H-MoS2 to 1 T-MoS2 enhances the conductivity. 2D layered graphene and mesostructure architecture facilitates the penetration and buffers the volume stress.