Nonlinear optical property and fluorescence quenching behavior of PVP capped ZnS nanoparticles co-doped with Mn2+ and Sm3+

ZnS nanoparticles co-doped with different percentages of Mn2+ and Sm3+ were synthesized by the chemical co-precipitation method using polyvinylpyrrolidone (PVP) as capping agent. Cubic zinc blende phase of the samples was confirmed from X-ray diffraction. The strong interaction between PVP and ZnS nanoparticles was studied from Fourier Transform Infrared (FTIR) spectrum. The band gap values of ZnS and co-doped ZnS nanoparticles were calculated from UV-Visible spectra. The photoluminescence spectra of pure ZnS nanoparticles showed an emission at 436 nm and when doped with Mn2+ and Sm3+ an extra peak with high intensity was observed at 596 am. On increasing the mole percentage of dopants the intensity of the extra peak showed an enhancement until a certain concentration and then a reduction with further increase in concentration. The binding parameters were determined by Stern-Volmer relation. The nonlinear absorption coefficients of the doped and undoped samples were calculated using Z-scan technique. (C) 2015 Elsevier B.V. All rights reserved.