Observation of Green Photoluminescence Suppression in ZnO Nanocrystals Embedded into Porous Opal

The photoluminescence and transmittance characteristics of ZnO nanocrystals embedded into voids of synthetic opal by using a technologically simple sol-gel method have been investigated. The uniform formation of ZnO nanocrystals inside an opal matrix was obtained after inltration a sample in deionized aqueous solution with zinc nitrate hexahydride precursor followed by thermal annealing. Suppression of photoluminescence intensity in the green spectral band is observed due to the inhibition of spontaneous emission originating through ZnO lattice defects such as oxygen vacancies and Zn interstitials. Despite the high density of crystal defects, ZnO nanocrystals embedded into photonic crystal exhibit a dominant ultraviolet-blue emission. KCI Citation Count: 4