Cd1-xDyxS semiconductor quantum dots: Structure, optical properties and energy transfer parameters

Dy3+ ions doped into CdS (Cd1-xDyxS) semiconductor quantum dots (QDs) were successfully synthesized using a wet chemical method. The presence of Dy3+ ions in CdS QDs was verified using Energy Dispersive X-ray spectroscopy (EDX). X-ray Diffraction (XRD) and absorption spectral analyses revealed that the as-synthesized QDs had a Wurtzite (WZ) structure with a particle size of approximately 4–5 nm. The optical properties of Dy3+ ions, ligand asymmetry and nature of the Dy3+-ligand bond in Cd1-xDyxS QDs were studied using excitation spectroscopy, photoluminescence (PL) spectroscopy and PL lifetime. The energy transfer processes from CdS host to Dy3+ ions and between Dy3+ ions, as well as the nature and mechanism of these processes were studied and explained in detail. The results of the analysis of CIE Chromatic coordinate diagram show that the Cd1-xDyxS QD is potential candidates for lighting applications because they can emit white light with suitable Dy concentration.