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Bismuth silicate Bi 4 Si 3 O 12 or BSO thin films were synthesized by pulsed laser deposition and a subsequent annealing treatment from a Bi-Fe-O and compared with films obtained with a pure Bi 2 O 3 target. BiFe-O amorphous thin films of different thicknesses were deposited on silicon substrates at room temperature and subsequently heat treated at 800°C at different times to study the phase transformations, keeping in all steps a constant oxygen atmosphere. After annealing, Bi-Si-O crystalline phases are formed in all cases with different synthesis kinetics. The Bi-Fe-O target clearly increases the synthesis kinetic of a textured BSO phase having a dissociation and precipitation of homogeneously distributed Fe 2 O 3 particles in the BSO matrix. The key aspects to obtain the Bi 4 Si 3 O 12 stoichiometric phase are both the film thickness and the heat treatment time to allow the reaction between the Bi 2 O 3 from the target and the SiO 2 obtained after the oxidation of the substrate. A deposition time of Bi-Fe-O for 120 and 30 min annealing fulfills the conditions to obtain the Bi 4 Si 3 O 12 stoichiometric composition and thus scintillation performance. The scintillation properties were measured by a fluorescence spectrophotometry. The stoichiometric Bi 4 Si 3 O 12 samples show that under 260 nm excitation the material exhibits a peak emission at 466.6 nm. These Bi 4 Si 3 O 12 thin films crystallize in eulytite phase with cubic structure (a = b = c = 10.291 Å ). The phase content was obtained by Rietveld analysis of X-ray diffraction patterns.

Fe 96−x Co x C 4 (x = 0, 10, 20, 30, 40 at. %) alloys were obtained by mechanical alloying of Fe, C and Co powders using high-energy milling. The structural and magnetic properties of the alloy system were analyzed by X-ray diffraction, Scanning Electron Microscopy (SEM), Vibrating Sample Magnetometer (VSM) and Mössbauer Spectrometry at room temperature. The X-ray diffraction patterns showed a BCC-FeCoC structure phase for all samples, as well as a lattice parameter that slightly decreases with Co content. The saturation magnetization and coercive field were analyzed as a function of Co content. The Mössbauer spectra were fitted with a hyperfine magnetic field distribution showing the ferromagnetic behavior and the disordered character of the samples. The mean hyperfine magnetic field remained nearly constant (358 T) with Co content.

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The formation of thin films based on TiO2 plays a fundamental role in research involving solar energy (solar cell and solar thermal collectors) and from the part environmental (photocatalysis-artificial photosynthesis as a source of clean energy). In this sense, our work has focused on the experimental details directed towards the method of obtaining, for which as a precursor salt Titanium Oxyacetylacetonate (IV) (Sigma Aldrich with 90 % purity) it has been used dissolved in methyl alcohol (Fisher Chemical with 99.8% purity) in 0.05 M molar concentration. The effect on deposited films was studied by varying airflow (2 L/min - 6 L/min) and substrate temperature (150 °C - 450 °C). For the Optical and structural characterization was used UV-VIS spectroscopy and X-ray diffraction techniques. From the analysis of the results was determined the energy band gap with values around 3.5 eV for all films. The Anatase phase with tetragonal structure was find it, refined using the Rietveld method that determined network parameters of a = 3.807617 Å, b = 3.807617 Å, c = 9.547797 Å, the thickness of the films ranged in a range between 70 nm - 150 nm whose values depended on the deposit conditions. The previous evidence allows concluding that this material can be used as an anti-reflective layer to be implemented in solar collectors.