The present work reports the synthesis and the characterization of cobalt oxide thin films obtained by chemical vapor deposition (CVD) on indium tin oxide (ITO) substrates, using a cobalt(II) β-diketonate as precursor. The complex is characterized by electron impact mass spectrometry (EI-MS) and thermal analysis in order to investigate its decomposition pattern. The depositions are carried out in a cold wall reactor in the temperature range 350-500 °C at different oxygen pressures, to tailor film composition from CoO to Co 3 O 4 . The crystalline nanostructure is evidenced by X-ray diffraction (XRD), while the surface and in-depth chemical composition is studied by X-ray photoelectron (XPS) and X-ray excited auger electron spectroscopy (XE-AES). Atomic force microscopy (AFM) is employed to analyze the surface morphology of the films and its dependence on the synthesis conditions. Relevant results concerning the control of composition and microstructure of Co-O thin films are presented and discussed.

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High-temperature proton conductors are promising as electrolytes for intermediate-temperature solid oxide fuel cells. Among them, BaCeO 3 -based materials have high proton conductivity but rather poor chemical stability. In contrast, barium zirconates are rather stable, but have poorly reproducible densities and conductivities. In this study, the investigation of BaCe 1ÀxÀy Zr x Y y O 3Àd solid solutions (x ¼ 0, 0.10, 0.20, 0.30, 0.40; y ¼ 0.15, 0.20) was undertaken, with the final aim of finding a composition having both high conductivity and good stability. The influence of the modified sol-gel Pechini synthetic approach on the powder morphology, and of a barium excess on the densification were demonstrated. Single-phase perovskite powders were prepared and high density pellets were obtained at temperatures lower than those commonly employed. Stability tests demonstrated that the Zr introduction into doped barium cerate greatly enhanced the chemical stability, particularly for Zr $ 20%. The proton conductivities, measured in a humidified H 2 /Ar atmosphere by impedance spectroscopy, were only slightly influenced by the Zr amount. Overall, BaCe 1ÀxÀy Zr x Y y O 3Àd solid solutions having Zr z 20-40% and Y z 15-20% showed good chemical stability and high conductivity.

Mixed proton and electron conductor ceramic composites were examined as hydrogen separation membranes at moderate temperatures (higher than 500 °C).

A novel single-source precursor, zinc bis(O-ethylxanthate), was employed for the CVD of ZnS-based thin films. The coatings were deposited on SiO 2 and SiO 2 /Si(100) substrates in a N 2 atmosphere in a cold-wall reactor in the temperature range 250± 400 C. The optical properties of the films were investigated by ultra violet-visible (UV-vis) absorption and Fourier transform infrared (FTIR) spectroscopies. The surface and in-depth chemical composition were studied by X-ray photoelectron spectroscopy (XPS), X-ray excited Auger electron spectroscopy (XE-AES), and secondary ion mass spectrometry (SIMS). Finally, atomic force microscopy (AFM) was employed to analyze the surface morphology of the coatings. Very thin films, with thickness less than 30 nm and no evidence of crystalline phases, were grown at temperatures of at least 300 C. Optical measurement showed that the coatings were highly transparent ( > 80 %) throughout the visible and IR spectral ranges.