Among transition metal dichalcogenides family, molybdenum disulphide (MoS2) nanomaterial has a vital role in two-dimensional field due to its intrinsic optical and electronic properties. In this study, we report a new top-down approach for synthesising MoS2 quantum dots (QDs). This strategy consists of liquid nitrogen (LN2) quenching of bulk MoS2 material followed by two processes, probe sonication and ultra-centrifugation. This approach is simple, cost effective and eco-friendly. The structural, optical and morphological properties of obtained MoS2 quantum dots were characterised. Photoluminescence spectra (PL) of the synthesised MoS2 QDs show blue light emission when excited with ultraviolet radiation (365 nm). A significant observation in this study is that, the peak position of photoluminescence (PL) emission spectra is independent of excitation wavelength. In addition, a higher fluorescence quantum yield was obtained for the present MoS2 QDs compared to MoS2 QDs prepared by other methods.
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