An experimental study: Role of different ambient on sulfurization of MoO₃ into MoS₂

Molybdenum disulfide (MoS₂) nanostructured thin films (NTFs) were synthesised by sulfurizing MoO₃ NTFs using three different non-conventional methods (named methods 1–3). Method 1 uses sulfur vapors, second employs H₂S/Ar gas and third adopts plasma of H₂S/Ar gas. HRTEM revealed formation of core–shell nanostructures with maximum shell thickness obtained in method 3. The samples showed uniform nanoflakes (NFs) throughout substrate, revealed by SEM, same as their precursor MoO_3. XRD and Raman analysis disclosed crystalline MoS₂ and degree of crystallinity was greatest in case of sulfurization in plasma ambient. Quantitative analysis of sulfurized films carried out by XPS shows presence of MoS₂ in all three methods with percentage found to be 18%, 87% and ∼100% respectively. The effect of sulfurizing ambient on its efficiency to convert MoO₃ into MoS₂ has been studied and it was found out that plasma ambient has resulted in high quality of MoS₂ NTFs based on parameters as crystallinity, purity, uniformity and stoichiometry control. - Highlights: • Comparison of three non-conventional methods of sulfurization. • Parameters used for comparison are crystallinity, purity, sulfurized thickness, uniformity and stoichiometry. • H₂S/Ar plasma based method came out to be best among other techniques. • A soft template reactions for sulfurization of MoO₃ nanoflake is proposed.