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In this paper SiO x thin films were deposited on Y-TZP ceramics by reactive magnetron sputtering technique in order to improve the adhesion properties between Y-TZP and resin cement for applications in dental prosthesis. For fixed cathode voltage, target current, working pressure and target-to-substrate distance, SiO x thin films were deposited at different oxygen concentrations in the Ar+O 2 plasma forming gas. After deposition processes, SiO x thin films were characterized by profilometry, energy dispersive spectroscopy (EDS), optical microscopy and scanning electron microscopy (SEM). Adhesion properties between Y-TZP and resin cement were evaluated by shear testing. Results indicate that films deposited at 20%O 2 increased the bond strength to (32.8 ± 5.4) MPa. This value has not been achieved by traditional methods.

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Hydrogen is an environmentally promising energy carrier, with a high potential for use in the mobility and energy sectors. However, large use of hydrogen still demands efficient and safe handling, transportation, and storage infrastructure. Short-contact-time reactors have been investigated as an alternative to produce a hydrogen-rich syngas close to its use. The control of the manufacturing process of such reactors and its influence on their performance are of great interest. Here, we investigated the effect of a washcoat in the Ni/Al2O3 short-contact-time reactors on the catalytic activity of steam reforming (SR) and partial oxidation (POX) of ethanol. The influence of the coating process on the washcoat thickness and catalyst morphology was explored. The catalytic activity was tested in order to understand the effect of the washcoat on ethanol conversion, product distribution, and improvement of hydrogen production. Results indicated the increase in the surface area as the monolith is coated, which improved the Ni dispersion and consequently produced smaller average size crystallites. The effect of the washcoat was evidenced on the product selectivities, by the increase of the activity for the C–C bond breaking, which leads to the production of C1 species. The Ni/Al2O3 monolith was catalytically active for ethanol SR and is revealed to be an alternative route for simultaneously producing acetaldehyde and hydrogen from POX in short-contact-time reactors.

In this paper, nitrogen-doped TiO2thin films were deposited by DC reactive sputtering at different doping levels for the development of dye-sensitized solar cells. The mechanism of film growth during the sputtering process and the effect of the nitrogen doping on the structural, optical, morphological, chemical, and electronic properties of the TiO2were investigated by numerical modeling and experimental methods. The influence of the nitrogen doping on the working principle of the prototypes was investigated by current-voltage relations measured under illuminated and dark conditions. The results indicate that, during the film deposition, the control of the oxidation processes of the nitride layers plays a fundamental role for an effective incorporation of substitutional nitrogen in the film structure and cells built with nitrogen-doped TiO2have higher short-circuit photocurrent in relation to that obtained with conventional DSSCs. On the other hand, DSSCs built with nondoped TiO2have higher open-circuit voltage. These experimental observations indicate that the incorporation of nitrogen in the TiO2lattice increases simultaneously the processes of generation and destruction of electric current.

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Niobium doped dititanium trioxide (Ti 2 O 3 :Nb) films were deposited on glass substrates, through grid-assisted magnetron sputtering. The Ti 2 O 3 :Nb films were characterized by X-ray diffraction (XRD), electrical conductivity and optical properties. Film deposition was carried out in two different substrate bias modes: DC and unipolar pulsed. Results show that the negative-pulsed mode improves conductivity and crystallinity. The XRD results show peaks corresponding crystallographic planes of Ti 2 O 3. No niobium oxide Nb x O y peaks were observed, which indicates that niobium oxide if formed, is amorphous, and/or substituted Nb atoms remain in a solid solution within the Ti2O3 structure. It was observed that "as-deposited" Ti 2 O 3 :Nb films (without post annealing) are transparent and electrical conductive, with transmittance that reaches 60% in the visible light wavelength despite the considerable thickness of the film and a miminum resistivity of 2x10-2 Ω.cm which indicates that there is potential for application as Transparent Conductive Oxide (TCO).