ZnSe/ZnSe:Ag nanoparticles: synthesis, characterizations, optical and raman studies.

ABSTRACT

Nanoparticles (NPs), grown in liquid media, stand out over other classes of inorganic nanomaterials due to the high degree of control with which their crystal structure, size, shape, and surface functionalities can be engineered in the synthesis stage and to the versatility with which they can be processed and implemented into a large spectrum of devices and processes. In present work pure and Ag-doped ZnSe NPs were successfully synthesized from the solution phase chemistry and investigated with respect to their structural and optical properties. The resulting powder consists of nanocrystalline particles were characterized by X-ray diffraction (XRD), UV-Visible spectroscopy, photoluminescence spectroscopy, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), energy dispersive X-ray analysis (EDX) techniques and Raman spectroscopy. A UV emission peak was observed from the excitons transition at 380 nm in the room temperature photo luminescent (PL) spectra. The blue emission band was assigned to the Zn interstitial and vacancy level transition. Even though Ag ions known to act as an efficient non-radiative loss center for near band gap emission (NBE), a decreased NBE is obtained at room temperature even for a nominal Ag concentration. XRD data analysis shows that the Ag dopant atoms are incorporated into the cubic ZnSe host lattice.