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N-doped TiO 2 thin films have been prepared by reactive RF magnetron sputtering at different pressures and with different compositions using a dual reactive gas mixture of nitrogen and oxygen. The morphological, optical, photo-electrochemical and photocatalytic properties have been studied in order to investigate the white light and visible light photoactivities of the films. Significant control over the band gap energy in the films was achieved by varying the deposition parameters. Photoelectrochemical characterization revealed improved white light photocurrent generation in nitrogen doped films prepared at low pressures. However, the visible light photocurrent generation showed improvement for all deposition pressures, and changed accordingly with the nitrogen incorporation. Photocatalytic measurements of a common chemical pollutant NMP (N-Methyl-2pyrrolidone) under different irradiation conditions provided evidence of improved photoactivity for samples prepared at high pressure, due to the increased active surface area and optimal nitrogen doping levels. Overall, this study showed a simple method to produce highly controllable nitrogen doping in different sites within TiO 2 showing improved visible light photoactivity and photo induced pollutant degradation. More interestingly, by investigating the effect of different nitrogen sites in nitrogen doped TiO 2, we have shown that the optimized conditions for photocatalysis do not correspond to those for water splitting.

Water stable plasma polymerized acrylic acid/methylene-bis-acrylamide (ppAA/MBA) thin films have been deposited with an atmospheric pressure air plasma jet, a fast technique to grow organic thin films. To increase the stability of the coatings, a cross-linking agent (MBA) was added to the precursor (AA), which was introduced with a home-made spraying system. The jet speed and pulse frequency of the discharge were investigated regarding the properties of the coatings. Two types of materials were obtained: in low energy conditions (high jet speed and low frequency) the films presented a water-soluble part with a certain organized structure. When more energy is supplied to the growing films, a more polymerized material with a more amorphous structure is obtained. Increasing the energy further leads to the deposition of a more crosslinked film with a better stability to water. In optimized conditions, no weight loss and no significant chemical change were noticed after soaking in water.

Surface treatment of polydimethylsiloxane (PDMS) with a rotative nozzle atmospheric pressure plasma jet (APPJ) was reported. Operating conditions were optimized by statistical design of experiments, using water contact angle and XPS as response variables; OES (optical emission spectroscopy) was used for plasma diagnosis. The nozzle‐PDMS distance and the torch speed were the most influencing parameters and were optimum at 6.6 mm and 10.3 m s−1, respectively. The extent of hydrophobic recovery of treated PDMS, investigated by water contact angle measurements, was less than what reported in the literature for this amorphous polymer. However, the APPJ treatment proposed in this paper is meant to be inserted in line for a homogeneous surface treatment of PDMS for enhanced adhesion improvement to coatings or adhesives.

Multi-layered thin films of TiO 2 and TiN were created by RF reactive magnetron sputtering and were compared with homogeneous thin films of N doped TiO 2 having the same thickness. The crystalline, chemical, optical and photoactive properties were measured and discussed in detail. The number of bilayers was kept constant either 9 or 18 bilayers, but the overall composition (TiN to TiO 2 ratio) was varied. The TiN and TiO 2 layer thicknesses were controlled systematically in order to produce films with TiN to TiO 2 ratio ranging from 5% to 28%. The TiN/TiO 2 ratio was controlled for both bilayers in order to get the best synergic effect of light absorption/reflection and charge separation based on the generation of the photo-electrochemical current and the photocatalytic activity under UV and visible light. A maximum photocurrent generation was found for thin films having a TiN/TiO 2 ratio of 21% and 28% for the 9 bilayer and the 18 bilayer films, respectively. The superiority of the configuration of the 18 bilayer has been confirmed by studying the photocatalytic activity. The photoactive improvement of the bilayered thin films as compared to non-doped TiO 2 is the result of the enhanced charge separation at the heterogeneous junction, interfacial effects between TiN and TiO 2 , which is found to depend on the thickness of the TiN layers. Electronic as well as optical approaches have been presented to explain the superiority of the bilayers strategy. This study has shown that a bilayered morphology of TiN and TiO 2 can significantly enhance the photocatalytic and photoelectrochemical behavior of TiO 2 under visible light illumination conditions which is applicable to numerous fields.

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Thin films of TiN were prepared via RF magnetron reactive sputtering at various deposition pressures. The characteristics of the plasmas were measured by optical emission spectroscopy to optimize the conditions for the deposition of TiN coatings. After deposition, the thin films were annealed in a closed furnace at several different temperatures, and revealed the formation of different phases of TiO2. The resulting TiN/TiO2 thin films showed drastic changes in their crystal structure, optical properties, and photoelectrochemical performance. By examining how the deposition pressure and postdeposition annealing conditions affected the TiN film structure and performance, samples were prepared to optimize visible light absorption and activity. A model for the oxidation process was proposed which described the structural change from TiN to TiO2 through optical, morphological, and crystalline characterization. This study has systematically shown the ability to tailor the optical, crystalline, and photoactive properties of TiO2 by tailoring the intrinsic properties of TiN thin films and subsequent annealing. These results can be utilized for many solar driven optoelectronic devices.

Thin films of fluorocarbon were deposited on polyethersulfone membranes via argon plasma sputtering of a poly (tetrafluoroethylene) (PTFE) target in an RF magnetron plasma reactor. The obtained deposited ultrathin coatings had nanoscale roughnesses and high degrees of fluorination.The intensity of fluorine atom in plasma environment during fluorocarbon deposition was investigated. Depending on the deposition conditions comprising working gas pressure, applied RF power, and distance between the target and the substrate, polymeric films with different chemical compositions and/or morphologies were obtained. The morphologies of the films were analyzed by means of SEM, XPS, and AFM. The results suggested that the sputtered film deposited at a higher pressure and longer target-substrate distance and moderate RF power had a surface composition and chemical structure closer to those of the PTFE film. The treated hydrophobic PES membranes with water contact angles as high as 115° were applied for the first * Corresponding author.