Structural and electrochemical mechanism study of layered MoTe2 anode material for sodium-ion battery

Abstract

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 (MoTe2) has the ability for sodium-ion storage properties due to its comparative more interlayer spacing. In this study, the MoTe2 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 MoTe2 cycled electrodes to understand the needed electrochemical mechanism. The initial discharge capacity of the MoTe2 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 MoTe2 have the unique capability to deliver superior sodium-ion storage ability for its utility as an anode material for sodium-ion battery.