Characterization of Mn, Cu, and (Mn, Cu) co-doped ZnS nanoparticles

Mn, Cu, and (Mn, Cu) co-doped ZnS nanoparticles were prepared using the hydrothermal method at 180°C. A hexagonal structure of synthesized ZnS nanoparticles was confirmed using X-ray diffraction. Scanning electron microscopy confirmed the morphology and elemental analysis of the ZnS nanoparticle as a spherical shape. Two luminescence peaks appearing in the photoluminescence spectrum of the pure ZnS nanoparticles were shown at 379 and 472 nm, which are attributed to the recombination of the defect states of ZnS. A third peak also appears on the doped ZnS samples. It was identified at about 556 and 580 nm for Cu- and Mn-doped ZnS, respectively, which are commonly attributed to the recombination of charge carriers. With the (Mn, Cu) co-doped ZnS, the emission peak showed a shift to longer wavelengths.