Stoichiometric dependent MoS2 with tuned edge sulfur as excellent anode material for Li-ion batteries

Abstract

Molybdenum disulfide (MoS₂) has emerged as a promising negative electrode due to its excellent capacity in Li-ion- battery applications. The optoelectronic and electrochemical properties of hydrothermally grown MoS₂ micro-flower (flakes) have been intensively investigated. Still, the influence of stoichiometric ratio on the electrochemical and optical properties has been largely ignored, especially in Li-ion battery applications. Here, in this context, we systematically vary the stoichiometric ratio of sulfur precursor (Thiourea) in three distinct synthesized MoS₂ samples, A1, A2, and A3, via controlled hydrothermal reaction and investigate the associated changes in the electrochemical properties of synthesized MoS₂. X-ray photoelectron spectroscopy was employed to measure relative variations in stoichiometry and the existence of MoS₂ species. Sample A1 possesses the lowest sulfur content, and it shows a higher specific capacity (2185 mAhg⁻¹) and coulombic efficiency (88.11 %) as an anode material in Li-ion battery application.