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Rare earth complex Eu(phen)2Cl3·2H2O synthesized by precipitation method was incorporated into MCM-41 mesoporous molecular sieves which were synthesized via a hydrothermal method. Hybrid inorganic/organic mesoporous luminescent material Eu(phen)2/MCM-41 has been characterized by XRD, TEM, IR, UV-visible spectra and fluorescence spectra. Results indicated that the hybrid mesoporous material has typical structure of MCM-41 and retains the same pore structure as MCM-41 after the assembly process. The fluorescence spectra of these materials present a series of narrow lines assigned to 5D0 → 7F0,1,2,3,4 transitions. The high emission intensity observed is a promising property for application of the rare earth complex in technological luminescent devices.

Ge doped ZnO films have been deposited on Si(1 0 0) substrates by alternate rf sputtering of ZnO and Ge. The effects of doping and annealing on the optical and structural properties have been investigated by means of X-ray diffraction and photoluminescence (PL) spectra. With the increasing annealing temperature, the intensity of the ZnO(0 0 2) diffraction peak increases, indicating that the crystalline quality of the film improves. The samples annealed at 800 and 1000 °C there appear the GeO and GeO2 diffraction peaks, and the intensity of the near ultra-violet emission at 395 nm increases greatly, while a weak yellow emission appears at 590 nm. The near ultra-violet emission could be attributed to the GeO color centers and exciton recombination. The yellow peak is probably related to Ge incorporated in the ZnO structure.