Laser-assisted hydrothermal synthesis of MoS2 nanosheets under different laser energies and potential application in nonlinear optics

Abstract

The main aim of this work is the investigation and evaluation of the structural, morphological, molecular structural, chemical-bond, dielectric, linear, and nonlinear optical behavior of MoS2 nanosheets synthesized using a laser-assisted hydrothermal method when irradiated at different laser energies. The successful formation of the hexagonal phase of MoS2 was confirmed by using XRD analysis. The calculations of the optical constants and dielectric coefficients of MoS2 nanosheets were performed by FTIR measurements using Kramers-Kronig relations. MoS2 nanosheets were pumped using a continuous-wave Nd:YAG laser source operating at 532 nm to consider the optical absorptive and refractive nonlinearity through the open and closed-aperture Z-scan technique, respectively. A negative nonlinearity and a third-order nonlinear optical susceptibility of the order of 10−5 esu were obtained for MoS2 nanosheets. An increase in all nonlinear optical parameters was observed when MoS2 nanosheets were irradiated with higher laser energy during the synthesis process. The findings of the current research open a new path to improving two-dimensional nanomaterials leading to the development of nanophotonic devices.