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Abstract: The extension of pulsed laser deposition to the synthesis on Ti substrates of β-tricalcium phosphate (β-TCP) coatings doped with manganese is reported. Targets sintered from two crystalline Mn-doped β-TCP powders (with the composition Ca2.9Mn0.1(PO4)2 and Ca2.8Mn0.2(PO4)2) were ablated with an UV KrF* (λ =248nm, τ ∼7ns) laser source. X-ray diffraction and energy dispersive X-ray spectroscopy investigations showed that the films, while prevalently amorphous, had a Ca/P ratio of about 1.50–1.52. Scanning electron microscopy analyses revealed a rather homogeneous aspect of the coatings which were molded to the relief of the chemically etched Ti substrate. Fluorescence microscopy was applied to test the proliferation of mesenchymal stem cells grown on the obtained biostructures. Our investigations found that, even 14 days after cultivation, the synthesized films were not cytotoxic. On the contrary, they showed excellent bioactivity, as demonstrated by the neat spread of the cells over the entire surface of Mn-doped β-TCP. When tested in osteoprogenitor cell culture, the Ca2.8Mn0.2(PO4)2 samples revealed a higher potential for proliferation and better viability compared with Ca2.9Mn0.1(PO4)2. [Copyright &y& Elsevier]

Abstract: The influence of target–substrate distance during pulsed laser deposition of indium zinc oxide (IZO), indium tin oxide (ITO) and aluminium-doped zinc oxide (AZO) thin films grown on polyethylene terephthalate (PET) substrates was investigated. It was found that the properties of such flexible transparent conductive oxide (TCO)/PET electrodes critically depend on this parameter. The TCO films that were deposited at distances of 6 and 8cm exhibited an optical transmittance higher than 90% in the visible range and electrical resistivities around 5×10−4 Ωcm. In addition to these excellent electrical and optical characteristics the films grown at 8cm distance were homogenous, smooth, adherent, and without cracks or any other extended defects, being suitable for opto-electronic device applications. [Copyright &y& Elsevier]

Abstract: The synthesis by pulsed laser deposition technique of zinc oxide thin films suitable for gas sensing applications is herein reported. The ZnO targets were irradiated by an UV KrF* (λ =248nm, τ FWHM ∼7ns) excimer laser source, operated at 2.8J/cm2 incident fluence value, whilst the substrates consisted of SiO2(001) wafers heated at 150°C during the thin films growth process. The experiments were performed in an oxygen dynamic pressure of 10Pa. Structural and optical properties of the thin films were investigated. The obtained results have demonstrated that the films are c-axis oriented. Their average transmission in the visible-infrared spectral region was found to be about 85%. The equivalent refractive indexes and extinction coefficients were very close to those of the tabulated reference values. Doping with 0.5% Au and coating with 100 pulses of Au clusters caused but a very slight decrease (with a few percent) of both transmission and refractive index values. The coatings with the most appropriate optical properties as waveguides have been selected and their behavior was tested for butane sensing. [Copyright &y& Elsevier]