Dy 2O 3 nanoparticles were synthesized at room temperature through soft chemical route using dysprosium acetate hexahydrate and hexamethylenetetramine as starting materials. As-synthesized Dy 2O 3 nanoparticles were calcined up to 600°C and the samples were subjected to various characterizations. The decomposition course of as-prepared particles and the formation process of Dy 2O 3 were studied by TG/DTA. The cubic bixbyite phase formation of Dy 2O 3 nanoparticles was confirmed by XRD results. The particle size and morphology were investigated by TEM. The composition and surface passivation were confirmed by EDS and FTIR studies, respectively. The possible formation mechanism has been discussed based on the experimental results. Bandgap of the material was estimated from the UV-vis absorption spectra. A blue-shift was observed in the absorbance as a result of quantum confinement effect, which was supported by PL spectra. © 2012 Elsevier B.V. All rights reserved.