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

• 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.

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 MoO3. 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.