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This study reports on deposition of asymmetrical substituted meso -phenyl porphyrin, 5-(4-carboxyphenyl)-10,15,20-triphenylporphyrin (CPTPP) thin films by matrix-assisted pulsed laser evaporation (MAPLE) on screen-printed electrodes, aiming for histamine detection. Raman spectrometry confirmed that CPTPP chemical structure was preserved in MAPLE-deposited thin films at 200 mJ/cm 2 laser fluence. Atomic force microscopy topography revealed that MAPLE-deposited thin films have a better coverage on the working electrode made of carbon compared to the ones obtained by dropcasting. Cyclic voltammetry demonstrated that CPTPP is an appropriate mediator for histamine detection in trichloroacetic acid solution. We proved that MAPLE serves as a soft technique in fabrication of porphyrin thin films and patterns. [ABSTRACT FROM AUTHOR]

Materials properties are the keystone of functional devices for energy including energy conversion, harvesting or storage. But to market new energy materials, the development of suitable processing methods allowing affordable prices is needed. Recently, a new approach to atomic layer deposition (ALD) has gained much momentum. This alternative approach is based on separating the precursors in space rather than in time, and has therefore been called Spatial ALD (SALD). With SALD, the purge steps typical of ALD are not needed and thus deposition rates a hundred times faster are achievable. Additionally, SALD can be easily performed at ambient atmosphere, thus it is easier and cheaper to scale up than conventional ALD. This opens the door to widespread industrial application of ALD for the deposition of energy materials for applications including solar energy, energy storage, or smart windows. SALD is presented here and examples of application to photovoltaics and transparent conductive materials are given. We show that SALD is capable of producing high-quality films fully suited for device integration. [ABSTRACT FROM AUTHOR]

Abstract: This work concerns the investigation of loading layers/substrate structures in order to determine the critical thickness at which Rayleigh wave characteristics of layers can be completely distinguished from those of the substrates. To do so, we first calculate Rayleigh velocity dispersion curves of several thin film materials (about thirty) deposited on different slow and fast substrates (Be, Al2O3, AlN, Si, SiO2, Mg, SiC, TiN, WC and Pyrex). Then, from the beginning of curve saturation (corresponding to the onset of intrinsic layer characteristics) we deduced normalized thickness transition for all layers/substrates combinations. Thus, we were able to deduce an analytical linear expression relating the critical thickness to combined effects of densities and velocities of both layers and substrates. Such a simple relation can be used, as an alternative method, to predict the transition critical thickness for any layer/substrate combination without the usual lengthy calculation of dispersion curves. To cite this article: Z. Hadjoub et al., C. R. Physique 9 (2008). [Copyright &y& Elsevier]

Abstract: Layer stiffening effects are studied via positive dispersion curves calculated for several layer/substrate configurations. The investigated layers (ZnO, Al, SiO2, Cr, Si, SiC, AlN, Si3N4 and Al2O3) deposited on Cu and/or Si substrates, showed two types of anomalous behaviour: velocities greater than the layer Rayleigh velocity and those smaller that the substrate Rayleigh velocity. The appearance and disappearance of these phenomena are analysed and quantified in terms of a suggested elastic parameter, ξ, which shows that their origin is due the combined effect of the velocities and densities of both the layer and the substrate. To cite this article: Z. Hadjoub et al., C. R. Physique 8 (2007). [Copyright &y& Elsevier]

Abstract: We briefly review the use and the derivation of Generalized Impedance Boundary Conditions (GIBC) in the case of thin dielectric coatings and in the case of strongly absorbing media, within the context of electromagnetic scattering problem at a fixed frequency. We then numerically test the validity and accuracy of these boundary conditions in the case of high absorption. A numerical treatment of the corner singularity is proposed to recover the accuracy of the GIBC for singular geometries. To cite this article: M. Duruflé et al., C. R. Physique 7 (2006). [Copyright &y& Elsevier]

Abstract: We report on the synthesis of nanocrystalline titanium dioxide thin films and powders by chemical and electrochemical deposition methods. Both methods are simple, inexpensive and suitable for large-scale production. Air-annealing of the films and powders at T =500 °C leads to densely packed nanometer sized anatase TiO2 particles. The obtained layers are characterized by different methods such as: X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Titanium dioxide TiO2 (anatase) phase with (101) preferred orientation has been obtained for the films deposited on glass; indium doped tin oxide (ITO) and quartz substrates. The powder obtained as the byproduct consists of TiO2 with anatase-phase as well. To cite this article: B. R. Sankapal et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: Structural and optical properties of TiO2 thin films prepared using a sol–gel process have been examined at different treatment temperatures and for different layer counts. XRD and Raman analyzes of our thin films of TiO2 show that 3 layer films crystallize in anatase and brookite phases, starting from the temperature of annealing 350 °C. The grain size calculated from XRD patterns varies from 6.7 to 23.5 nm. Refractive index and porosity are found to vary with treatment temperature and number of dippings. Our films, irrespective of treatment temperature and number of dippings, are transparent in the visible range and opaque in the UV region. To cite this article: R. Mechiakh, R. Bensaha, C. R. Physique 7 (2006). [Copyright &y& Elsevier]

Abstract: The preparation of mesoporous tungsten trioxide from tungstic acid and tungstic hexaethoxide precursors containing an added organic stabiliser via a sol–gel method is reported. The effect of annealing temperature and precursor species on the photoelectrochemical performance and the electrochromic colouration efficiencies has been discussed with the help of the characterisation of crystalline structure (through Raman microscopy) and surface morphology (through SEM imaging). To cite this article: R. Solarska et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: A model describing a macroscopic mechanism of the rupture of a free liquid film is introduced and analysed in the framework of the thin-film approximation. The process is shown to be driven by the surface-tension gradient arising when the rate of variation of the free-surface area due to external disturbances becomes comparable with the inverse surface-tension-relaxation time. The proposed mathematical description of the rupture phenomenon does not require the introduction of intermolecular forces into the equations of macroscopic fluid mechanics. To cite this article: Y.D. Shikhmurzaev, C. R. Mecanique 333 (2005). [Copyright &y& Elsevier]

Les couches de ZnO ont été déposées par la technique spray ultrasonique sur des substrats en verre chauffés à la température fixe 350 °C, en utilisant l'acétate de zinc avec une molarité de 0.1mol/l. Notre intérêt porte sur l’étude de l’influence du dopage sur les propriétés structurales, optiques et électriques de ces couches. Pour cela, nous avons utilisé la diffraction des rayons X pour les caractérisations structurales, la spectroscopie de transmission optique UV–Visible pour les caractérisations optiques et la technique de deux pointes pour les caractéristiques électriques de nos films. L’analyse structurale a montré que les films déposés ont une orientation préférentielle selon la direction (002). Les spectres de transmission UV- Visible confirment qu’il est possible d’obtenir de bons films transparents de ZnO avec une transmittance de 70 à 85% dans le visible. La caractérisation électrique, réalisée à l'aide de la technique de deux pointes, a donné une conductivité électrique maximale de 0.27 (Ωcm)-1 obtenue pour le film dopé à 8 % Al. [ABSTRACT FROM AUTHOR]