Enhancement of band-edge luminescence and photo-stability in colloidal CdSe quantum dots by various surface passivation technologies

Gelatin stabilized and AOT (sodium dioctyl sulfosuccinate) coated colloidal CdSe quantum dots (QDs) have been synthesized in aqueous solution and in micelle solution respectively. Photoluminescence spectra studies show that comparing to gelatin stabilized CdSe QDs, organic AOT stabilized CdSe QDs exhibit an enhancement of band-edge luminescence due to the surface passivation. We also use a higher band gap inorganic CdS for passivating layer on the core CdSe QDs. Our results indicate that CdSe/CdS QDs system shows both higher band-edge luminescence yield and greater stability under light illumination.