In this research, the structural phase composition and room temperature luminescence properties of terbium doped zirconium oxide powders obtained by solution combustion synthesis method are presented as a function of the terbium content. The doping with terbium ions was performed during the redox combustion process and after annealing at 900˚C during 20 hours. With the incorporation of the terbium ions into the zirconium oxide host, the stabilization of the high temperature tetragonal crystalline phase, as determined by x-ray diffraction technique, was obtained. Under ultraviolet radiation a bright green luminescence was observed at room temperature corresponding to the (4f) electron configuration of the Tb 3+ ion, namely the electronic transitions 5 D 4 → 7 F n with n = 3-6. In addition, the undoped ZrO 2 material showed green photoluminescence with high intensity.

Pure, and Europium ion doped Zinc oxide nanocrystals (ZnO:Eu 3+ ) were synthesized by a solution combustion technique. The X-ray diffraction patterns (XRD) reveals the existence of the Eu 2 O 3 phase. From the results of both, X-ray diffraction and photoluminescence spectra (PL) reveal that Eu 3+ ions successfully substitute for Zn 2+ ions in the ZnO lattice, moreover, when the amount of doped Europium was varied, this changes are showed in changes in the luminescence intensity. The PL is broad and a set of colors was emitted which originates from ZnO and the intra 4f transitions of Eu 3+ ions. The existence of the Zn-O, Eu 3+ -O and O1s bonding energies were confirmed by X-ray photoelectron spectroscopy (XPS) technique. The samples morphology was registered by a scanning electron microscopy (SEM) technique, and reveals that Europium ions are present on the surface of the ZnO nanocrystals.

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