Physio-chemical influence of high electron-phonon coupling induced by 120 MeV Ag9+ SHI irradiation on exfoliated MoS2 - PVA nanocomposite films for achieving remarkable electrical conductivity for potential application in organic electronics

Swift heavy ion (SHI) irradiation technology is known to enhance the optical, electronic, mechanical, and electrical properties in polymer nanocomposites by the virtue of electron-phonon coupling. In the present work, Molybdenum disulphide (MoS2), a two-dimensional metal dichalcogenide, has been exfoliated via liquid-phase exfoliation using N-methyl-2- pyrrolidone (NMP) as the solvent that yielded nanosheets of around 2-4 layers as depicted by HR-TEM images. MoS2 - PVA free-standing films were prepared by wet chemical technique i.e. solution casting method and irradiated by focussed high-energy Ag9+ ion beam at fluence range of 1E10- 3E11 ions/cm(2). As a consequence, the structural modification was observed by X-Ray diffraction studies that showed the shift of (002) plane of MoS2 while Raman studies indicated the decrease of degree of disorderness at fluence 1E10 ions/cm(2). SHI irradiation has found to induce a two-order increase in the electrical conductivity yielding a 9.7 E-3 S/cm against that of the pristine films at 2.6E-5 S/cm. The enhanced conductivity is attributed to the induced dispersion and annealing of MoS2 nanosheets in the PVA matrix due to the interaction of 120 MeV Ag9+ ion beam irradiation as explained by Thermal spike model.