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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.

Titanium Carbide TiC x was deposited onto quartz substrates by the chemical vapour deposition (CVD) method. TiC x thin films were obtained from titanium tetrachloride (TiCl 4) and toluene (C 6 H 5 CH 3) as carbon source. Deposits were carried out in the range of substrate temperatures from 300 to 1100 C, with a source gas molar ratio (C 6 H 5 CH 3 /TiCl 4 + C 6 H 5 CH 3) of 0.8. There was two deposit processes; the first was to carry out without nickel as catalyst and the second with nickel as catalyst. Results showed that the effect of nickel as catalyst is very relevant to obtain TiC x. TiC 0.87 thin films, 0.5 m thickness, were obtained for deposition temperatures above 900C using nickel as catalyst. In this case a cubic structure, with a lattice parameter of 4.327 Å and a hardness of 2900 Vickers, was obtained at 1100 0 C. whilst for substrate temperatures between 300 to 900°C with nickel as catalyst amorphous carbon samples were obtained. For the samples prepared without the presence of the nickel as catalyst only C amorphous thin films were obtained for all deposit temperatures.

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.