Structural and electrochemical mechanism study of layered MoTe_2 anode material for sodium-ion battery

摘要

Sodium-ion battery has shown hope in the field of future rechargeable battery technology due to its low-cost and abundance. Among the existing anode materials, layered transition metal dichalcogenides have the potential for sodium-ion batteries due to their interesting properties such as specific capacity, structural stability, and accessible layered structure. Among the existing 2D layered materials Molybdenum ditelluride (MoTe_2) has the ability for sodium-ion storage properties due to its comparative more interlayer spacing. In this study, the MoTe_2 polycrystalline powder sample has been synthesized by a solid-state route and the crystallographic and morphological analysis have been carried out by Synchrotron X-ray diffraction (SXRD), X-ray absorption near edge structure (XANES), FE-SEM, EDS etc. SXRD patterns have revealed the well crystalline structure of the material having the hexagonal structure. Further, X-ray absorption near structure (XANES) was conducted to study the electronic nature of MoTe_2 cycled electrodes to understand the needed electrochemical mechanism. The initial discharge capacity of the MoTe_2 powder showed an excellent capacity of Na-ion storage 326 mA h g~(-1) at a current density of 1.0 A g~(-1) and continued to 40 cycles with 264 mA h g~(-1) capacity. The obtained results showed the well-developed two-dimensional layers of MoTe_2 have the unique capability to deliver superior sodium-ion storage ability for its utility as an anode material for sodium-ion battery.