Nowadays 2-dimensional transition metal dichalcogenides (TMDCs) (Eg, MoS2, MoSe2, WS2, and WSe2) have attracted significant attention due to their interesting optical and electrical properties . TMDCs have layered structure held together by weak van der Waal’s forces. These materials possess an intrinsic indirect bandgap of ≈ 1.2 eV (for MoS2) in bulk form and ≈ 1.8 eV when reduces to a monolayer. Thus, the band gap in monolayer lies in the visible region of the spectrum, suggesting their use in light-sensitive applications. In bulk MoS2, the photoluminescence emission is quite feeble to be detected but the emission intensity is enhanced significantly when it is reduced to monolayers/nanostructures form . This enhancement is attributed to the direct band gap and quantum confinement effects in TMDCs nanostructures. In addition to size, various other factors like strain can also influence the band gap and hence can help in tuning the emission from these nanostructures .
Here, we report the synthesis of strained MoS2 nanostructures by using high energy ball milling and probe sonicator. XRD data revealed the shift in peak position implying the presence of strain in these nanostructures. This was further corroborated by the shift in Raman peaks. The blue-shift in UV-Vis absorption spectra is accredited to the combined effect of quantum confinement and strain in the lattice. The obtained emission spectra agree with the absorption data. The data suggest that rightly tuned MoS2 nanostructure can be used for light sensitive applications.
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