Strong luminescing CdSe nanoparticles by surface modification with cadmium (II) hydrous oxide

CdSe nanoparticles were prepared by simply mixing Na₂SSeO ₃ solution with CdSO₄ solution under [Cd ²⁺]/[Se^2-] (Cd/Se) ratio of 1.2 at room temperature. The nanoparticles had an average size of 2.3 nm and showed fairly strong photoluminescence (PL) with a peak at 539 nm. Deposition of cadmium (II) hydrous oxide on the CdSe nanoparticles increased photoluminescence quantum yield from 3.1 to 34.8 %, in comparison to Rhodamine 6G aqueous solution. Both of the CdSe nanoparticles and the cadmium (II) hydrous oxide deposited on CdSe nanoparticles were characterized as of cubic structure from XRD data and the electron diffraction (ED) patterns. Also, the reason for the photoluminescence enhancement was simply elucidated.