Preparation and excitonic properties of high quality organic-inorganic nanocomposite CdSe nanocrystals

TOPO (trioctyl phosphine oxide) capped-CdSe nanocrystals were prepared chemically by injecting organometallic reagents into a hot coordinating solvent over a range of optical absorption peaks of 482 ~ 580nm For limited size range of nanocrystals, we have succeeded to synthesize high quality nanocrystals which show fairly sharp excitonic spectral features, by controlling the particle size with the concentration of precursors. Overcoating of ZnS following the synthesis of CdSe nanocrystals have lead to a large enhancement of the fluorescence intensity (quantum efficiency).