Modifications of optical, structural, chemical and morphological properties of molybdenum disulfide (MoS2) sputtered thin films under high dose gamma radiation

Abstract

Molybdenum disulfide (MoS2) is considered to be a promising member of Transition metal dichalcogenides (TMDCs) displays significant physical and chemical peculiarities that make it promising candidate for extensive applications in nano and micro optoelectronic device applications, energy harvesting and light and gas detection devices. In the present work, we illustrated the influence of gamma ray irradiation on optical, morphological, structural and electronic peculiarities of 2D MoS2 thin films. 2D MoS2 thin films were grown by DC sputtering technique. The synthesized thin films samples were exposed to gamma radiation with 1500 kGy dose. There are significant structural and morphological alterations occur in thin films of MoS2 after exposure to gamma irradiation. From the absorption spectra Urbach energy, indirect optical band gap energy, absorption edge, and extinction coefficient were calculated. Alterations that occur in optical, structural, morphological and electronic parameters after the exposure of gamma irradiation have been corresponding with radiation instigated compositional and structural defects. The peculiarities of virgin and gamma exposed MoS2 thin films with 1500 kGy gamma-ray dose from Co-60 source were studied by UV spectrophotometer, X-ray diffraction (XRD), Rutherford Backscattering Spectroscopy (RBS), X-Ray photoelectron spectroscopy (XPS), Photoluminescence (PL) spectroscopy, Atomic Force Microscopy (AFM), Fourier-transform infrared spectroscopy (FTIR).