Structural, optical, and magnetic properties of Mn-doped ZnS nanoparticles

Abstract

Undoped and Mn-doped ZnS nanoparticles were successfully prepared through a coprecipitation method at low-temperature processing. The X-ray diffraction patterns reveal that the undoped and Mn-doped ZnS nanoparticles have polycrystalline nature with cubic ZnS structure. Furthermore, the lattice constant of the ZnS nanoparticles increases with an increase in the Mn doping concentration. Transmission electron microscope images demonstrated the as-synthesized nanoparticles have particle size ranging from 3 to 5 nm with spherical-shaped particles. Optical band gap values were found to increase from 3.32 to 3.50 eV with the increasing Mn doping concentration. The magnetic properties of undoped and Mn-doped ZnS samples were studied using the vibrating sample magnetometer at room temperature. The synthesized undoped ZnS nanoparticles exhibit ferromagnetism, while Mn-doped ZnS nanoparticles showed paramagnetism at room temperature. Moreover, the saturation magnetization of Mn-doped ZnS samples is higher compared to undoped ZnS. The present synthesis technique to produce high-crystalline quality Mn-doped ZnS nanoparticles and prepared nanoparticles has great potential applications in spintronic and optoelectronic devices.