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We report the detection of 100 ppm of butane in superatmospheric N2 or air with an m-lines setup. The sensing elements are ZnO-nanostructured coatings prepared by pulsed laser deposition. The deposition technique was optimized to obtain highly transparent films of 1 cm2 in area and several hundreds nanometer thick. ZnO structures preserve gas sensitivity even when deposited at room temperature. Refractive index variations down to 0.005 were detected and typical variations of about 20% were induced during ZnO film-butane contact. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 and Pt doped TiO2 thin films were grown by pulsed laser deposition on 〈001〉 SiO2 substrates. The doped films were compared with undoped ones deposited in similar experimental conditions. An UV KrF* (λ =248nm, τ FWHM ≅20ns, ν =2Hz) excimer laser was used for the irradiation of the TiO2 or Pt doped TiO2 targets. The substrate temperatures were fixed during the growth of the thin films at values within the 300–500°C range. The films’ surface morphology was investigated by atomic force microscopy and their crystalline quality by X-ray diffractometry. The corresponding transmission spectra were recorded with the aid of a double beam spectrophotometer in the spectral range of 400–1100nm. No contaminants or Pt segregation were detected in the synthesized anatase phase TiO2 thin films composition. Titania crystallites growth inhibition was observed with the increase of the dopant concentration. The average optical transmittance in the visible-infrared spectral range of the films is higher than 85%, which makes them suitable for sensor applications. [Copyright &y& Elsevier]

Abstract: Anatase phase titanium dioxide (TiO2) thin films were grown by pulsed laser deposition on 〈001〉 SiO2 substrates. An UV KrF* (λ =248nm, τ FWHM ≅20ns, ν =2Hz) excimer laser was used for the irradiation of the TiO2 targets. The substrates were kept at room temperature or heated during the film deposition at values within the 100–500°C range. The crystalline quality of the films and their chemical composition were investigated by X-ray diffractometry and energy dispersive X-ray spectroscopy. The optical properties were studied by a double beam spectrophotometer in the spectral range of 400–1200nm. At substrate temperatures higher than 300°C, the structure of the deposited thin films changes from poorly to well crystallised, corresponding to the tetragonal TiO2 anatase phase. The average optical transmittance in the visible-infrared spectral range of the films is higher than 85% which makes them suitable for sensor applications. [Copyright &y& Elsevier]

We report the film deposition of Poly(D,L-lactide-co-glycolide) (PLGA) particle systems by matrix assisted pulsed laser evaporation (MAPLE) technique. PLGA+polyvinyl alcohol (PVA), PLGA+PVA+ bovine serum albumin (BSA) and PLGA+PVA+chitosan (CH) nanoparticles were prepared by an oil-in-water emulsion-diffusion-evaporation method. The average diameter of PLGA particles was between 180-250 nm. The coatings were obtained by laser evaporation of frozen targets prepared by mixing appropriate PLGA aqueous suspensions and dimethyl sulfoxide (DMSO) in three ratios. Depending on the DMSO content, we deposited PLGA particles embedded into polymeric layer mainly obtained due to the entirely or partially dissolving of nanoparticles into the initial solution. In vitro results showed that the distribution and morphology of osteoblast-like SaOs-2 cells on some PLGA particle coatings were similar with that of the positive control. The purpose of this study was to develop layers of PLGA particles for local controlled drug delivery. [ABSTRACT FROM AUTHOR]

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]

Indium Zinc Oxide compositional libraries were fabricated by combinatorial pulsed laser deposition technique on glass substrate at room temperature. Two pairs of targets with In atomic concentrations, In/(In+Zn), of 28 at.% and 56 at.% or 42 at.% and 70 at.% were employed. A high transparency was observed for all the coatings with transmittance values better than 95%. The maximum thicknesses of the samples, inferred by spectroscopic ellipsometry, were within the 174-310 nm range for the simple PLD films, whereas in case of combinatorial PLD coatings were 341 or 467 nm. Energy dispersive X-ray spectroscopy revealed that In content in the combinatorial films was in the 27-52 at. % range. From atomic force microscopy histograms we evidenced a decrease of the RMS roughness down to 1 nm with the increase of the In content. As a result of the compositional library studies two minimum values of the electrical resistivity were identified at 2.3×10-3 Ω·cm and 8.6 ×10-4 Ω·cm, which correspond to 28.8-29.5 at.% and 44-49 at% range of Indium content. [ABSTRACT FROM AUTHOR]

Abstract: We report on the development of a modified gas diffusion layer for fuel cells consisting of a simple or teflonized carbon cloth pulsed laser deposited with metal oxide nanostructures designed to operate both as co-catalyst, and oxidic support for other electrochemically active catalysts. We selected TiO2, ZnO and Al2O3 doped (2wt.%) ZnO which were uniformly distributed over the surface of gas diffusion layers in order to improve the catalytic activity, stability and lifetime, and reduce the production costs of proton exchange membrane fuel cells. We evidenced by scanning electron microscopy and energy dispersive spectroscopy that our depositions consisted of TiO2 nanoparticles while in the case of ZnO and Al2O3 doped (2wt.%) ZnO transparent quasi-continuous films were synthesized. [ABSTRACT FROM AUTHOR]

Abstract: In this work we report on pulsed laser deposition (PLD) of chalcogenide thin films from the systems (AsSe)100−x AgI x and (AsSe)100−x Ag x for sensing applications. A KrF* excimer laser (λ =248nm; τ FWHM =25ns) was used to ablate the targets that had been prepared from the synthesised chalcogenide materials. The films were deposited in either vacuum (4×10−4 Pa) or argon (5Pa) on silicon and glass substrates kept at room temperature. The basic properties of the films, including their morphology, topography, structure, and composition were characterised by complementary techniques. Investigations by X-ray diffraction (XRD) confirmed the amorphous nature of the films, as no strong diffraction reflections were found. The film composition was studied by energy dispersive X-ray (EDX) spectroscopy. The morphology of the films investigated by scanning electron microscopy (SEM), revealed a particulate-covered homogeneous surface, typical of PLD. Topographical analyses by atomic force microscopy (AFM) showed that the particulate size was slightly larger in Ar than in vacuum. The uniform surface areas were rather smooth, with root mean square (rms) roughness increasing up to several nanometers with the AgI or Ag doping. Based upon the results from the comprehensive investigation of the basic properties of the chalcogenide films prepared by PLD and their dependence on the process parameters, samples with appropriate sorption properties can be selected for possible applications in cantilever gas sensors. [Copyright &y& Elsevier]

Abstract: Hydroxyapatite thin films were grown on layered structures by Pulsed Laser Deposition with the goal of investigating the interface of the ceramic film with the substrate. The latter consisted of Si/TiN/Ti sandwich structures. This multilayer substrate was also prepared by laser ablation earlier in the same experimental session. This particular type of structure was chosen in order to induce the in situ growth of hydroxyapatite directly onto freshly deposited Ti. We tried this way to avoid previous direct Ti exposure to air, hence its oxidation. The subsequent depositions of multilayers were performed with the aid of a carousel multi-target system mounted inside the irradiation chamber. This allowed for selecting in order the respective TiN, Ti and HA targets without opening the chamber between individual depositions. X-ray diffractometry, transmission electron microscopy and selected area electron diffractometry studies revealed the formation at the interface of a transition complex phase, 2 to 25nm thick, consisting of a mixture of TiO2 and CaP phase. The specific growth of TiN and Ti phases was also investigated. [Copyright &y& Elsevier]

Abstract: Aluminum nitride (AlN) thin films obtained by pulsed laser deposition (PLD) with a KrF* laser source (λ =248nm, τ ≥7ns) at a substrate temperature of 800°C and different values of ambient nitrogen pressure up to 10Pa have been studied. Precursors in the plasma plume were studied by optical multichannel emission spectroscopy. Emission spectra taken close to the target revealed the presence of atomic, single and multiple ionized Al and N species, as well as AlN molecular species. The analysis of the XRD patterns revealed that all films had a polycrystalline structure with mixed cubic and hexagonal phases. For AlN films deposited in vacuum, the structure is predominantly cubic with a small fraction of hexagonal phase. The cubic phase had a lattice parameter of 0.4045nm. The films deposited in nitrogen ambient have a cubic crystalline structure. At maximum nitrogen pressure of 10Pa the lattice parameter decreases to a =0.3949nm. [Copyright &y& Elsevier]

Abstract: We report the successful deposition of the porous polymer poly(d,l-lactide) by matrix assisted pulsed laser evaporation (MAPLE) using a KrF* excimer laser (248nm, τ =7ns) operated at 2Hz repetition rate. The chemical structure of the starting materials was preserved in the resulting thin films. Fluence played a key role in optimizing our depositions of the polymer. We demonstrated MAPLE was able to improve current approaches to grow high quality thin films of poly(d,l-lactide), including a porosity control highly required in targeted drug delivery. [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]

Abstract: We report the successful deposition of polycaprolactone polymer by MAPLE using a KrF* excimer laser (λ =248nm, τ =7ns). According to FTIR spectra the deposited films have similar chemical structure to the dropcast material. The fluence plays a key role in optimizing the performances of MAPLE-synthesized polycaprolactone structures. We demonstrated that MAPLE allows for controlling the morphology of films to the level required in targeted drug delivery of pharmacologic agents. [Copyright &y& Elsevier]