Structural, optical, and luminescence properties of Y3+ activated ZnS:Cl− nanoparticles.

The semiconducting ZnS:Cl⁻ nanoparticles coactivated with Y³⁺ ions were synthesized. The pure ZnS powders were prepared with conventional hydrothermal technique at 220 °C, activated with 25 mg/g NH₄Cl and coactivated with various concentrations of Y³⁺ ions. The impurity atoms incorporated ZnS powders were sintered at 960 °C under Ar ambient. The powders X-rays diffraction (PXRD) analysis for the synthesized powders showed the formation of mixed ZnS phases, and some fraction of ZnO phase. The existence of O atoms was confirmed by energy-dispersive X-rays (EDX) techniques as well. The average particle sizes of the synthesized nanoparticles were found to be about 500 nm by field emission scanning electron microscopy (FE-SEM) analysis. At room temperature, the emission spectra for the samples had broadband with maximum at 470 nm with excitation of 345 nm. An enhancement in the luminescence intensity was observed with an increase in Y³⁺ coactivator concentration up to 0.1 mg/g that can be assigned to the decrease in the concentration of traps. With further increase in Y³⁺ concentration, the light yield quenched. The synthesized ZnS_Cl⁻_Y³⁺ nanoparticles can be applied for various applications, such as optoelectronics, scintillation, photocatalysis, and sensing. [ABSTRACT FROM AUTHOR]