Enhanced optical limiting properties of graphene oxide-ZnS nanoparticles composites

Graphene oxide-ZnS (GOZS) nanocomposites were successfully prepared by solvothermal method. The microstructure, morphology and nonlinear optical properties of the obtained GOZS nanocomposites were characterized by XRD, Raman, SEM, TEM, Mapping, UV-vis and open aperture Z-scan test. The results show that ZnS particles with a diameter of about 20 nm are evenly distributed on the GO surface. And GOZS exhibited enhanced nonlinear absorption and optical limiting (OL) action under ultrafast (1030 nm, 340 fs) excitation. The theoretical nonlinear coefficients of GO, ZnS, GOZS(4:5), GOZS(2:5) and GOZS(1:5) at 20.8 GW/cm(2) are calculated as 27.6 cm/GW, 25.4 cm/GW, 554.9 cm/GW, 193.3 cm/GW and 117.1 cm/GW, respectively. The nonlinear performance of GOZS is 5-22 times higher than that of pure GO and ZnS, making it a potential optical limiting material. These results may be useful to design GOZS composites with better OL properties. (C) 2019 Elsevier Ltd. All rights reserved.