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Well dispersed Au NPs of narrow size distribution were obtained using an atmospheric DBD plasma torch. Ethanol used as solvent for Au precursor served as well as a C source for encapsulation of Au NPs preventing them from agglomeration.

Strontium titanate (STO) is a well-known oxide used in a wide variety of applications due to its excellent stability and optoelectronic properties. However, its integration in photoelectrocatalytic devices is limited by the lack of fast and scalable methods to produce robust films at a low temperature and atmospheric pressure. Herein, we report an atmospheric pressure plasma-enhanced chemical vapor deposition (AP-PECVD) approach for the synthesis of STO crystalline films and their applications for photoelectrochemical solar energy conversion. The film crystallinity, which plays a determinant role in the photoelectrochemical performance, was linked to the selected strontium precursor and injection method. Through thermal stability studies of the precursors [Sr(dpm), Sr(ipo), Sr(acac), and Ti(ipo)] and analysis of the solution droplet size, it was demonstrated that the closer thermal decomposition behavior and superior miscibility of the Sr(dpm) and Ti(ipo) precursors led to more homogeneous and crystalline films with the highest photoelectrochemical performance (16.5 μA cm

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A comparative study of as-deposited structural properties, oxidation and wear properties of industrially arc-deposited Ti-Al-N, Ti-Al-Y-N, Ti-Al-Ta-N and Ti-Al-Ta-Y-N is presented. In the as-deposited coatings, Ta leads to more compressive stress while Y reduces the compressive stress but increases the nanohardness. The nanohardness of Ti-Al-Ta-Y-N is shown to be dominated by Y while its oxidation rate is dominated by Ta. Interestingly, Ta specifically favours the growth of oxide at the interface between Al-rich and Ti-rich oxide layers.In 850°C ball-on-disk wear tests, there is a pronounced effect of the running-in stage, which in turn depends strongly on the oxidation properties of the coating.The transferability of these findings to industrial machining at higher temperatures are discussed.

The growth of thermoresponsive layers with the atmospheric pressure plasma-initiated chemical vapor deposition (AP-PiCVD) process is reported for the first time. N-vinyl caprolactam (NVCL) was successfully homopolymerized and copolymerized with ethylene glycol dimethacrylate (EGDMA), yielding water-soluble and water-stable thermoresponsive thin films, respectively. Strong chemical retention and high thermoresponsivity were achieved, highlighting the ability of AP-PiCVD to grow functional conventional homopolymers and copolymers.

Photocatalytic surfaces have the potentiality to respond to many of nowadays societal concerns such as clean H2 generation, CO2 conversion, organic pollutant removal or virus inactivation. Despite its numerous superior properties, the wide development of TiO2 photocatalytic surfaces suffers from important drawbacks. Hence, the high temperature usually required (> 450 °C) for the synthesis of anatase TiO2 is still a challenge to outreach. In this article, we report the development and optimisation of an ECWR-PECVD process enabling the deposition of anatase TiO2 thin films at low substrate temperature. Scanning of experimental parameters such as RF power and deposition time was achieved in order to maximise photocatalytic activity. The careful selection of the deposition parameters (RF power, deposition time and plasma gas composition) enabled the synthesis of coatings exhibiting photocatalytic activity comparable to industrial references such as P25 Degussa and Pilkington Activ at a substrate temperature below 200 °C. In addition, to further decrease the substrate temperature, the interest of pulsing the plasma RF source was investigated. Using a duty cycle of 50%, it is thus possible to synthesise photocatalytic anatase TiO2 thin films at a substrate temperature below 115 °C with a deposition rate around 10 nm/min.

Here, we describe a robust process aiming at conferring antibacterial properties on stainless steel through the covalent grafting of nisin, a natural antimicrobial peptide, onto a functional plasma thin film deposited by an atmospheric pressure dielectric barrier discharge process. The three different steps of the procedure, namely the deposition of a carboxyl rich thin layer, the surface activation by using a zero-length crosslinking agent and the nisin immobilisation, are reported and thoroughly characterised. A correlation between the carboxylic group surface concentration and the surface roughness onto the antibacterial properties of the layers is evidenced. Finally, IR analyses appear as a powerful analytical tool allowing us to validate the different chemical surface modifications, to confirm the relevance of the activation step to achieve a stable and homogenous peptide grafting over all the surfaces, as well as to investigate the secondary structure of immobilized peptides.

Bidentate diamine and amino‐alcohol ligands have been used to form solid, water‐soluble, and air‐stable monomeric copper complexes of the type [Cu(NH2CH2CH(R)Y)2(NO3)2] (1, R=H, Y=NH2; 2, R=H, Y=OH; 3, R=Me, Y=OH). The complexes were characterized by elemental analysis, mass spectrometry, infrared spectroscopy, thermal gravimetric analysis, and single‐crystal X‐ray diffraction. Irrespective of their decomposition temperature, precursors 1–3 yield highly conductive copper features [1.5×10−6 Ω m (±5×10−7 Ω m)] upon atmospheric‐pressure plasma‐enhanced sintering.

Prevention of bacterial adhesion and biofilm formation on the surfaces of materials is a topic of major medical and societal importance. In this study, an up-scalable atmospheric-pressure plasma assisted deposition method is introduced to produce a multicomponent coating towards the elaboration of antibacterial and anti-biofilm surfaces. Interestingly, from a single catechol-based monomer, high deposition rates of highly chemically reactive functional thin films bearing catechol as well as quinone groups are achieved. The catechol-bearing thin film allows the in situ silver nanoparticle formation, assessed by scanning electron microscopy and EDX, whilst the enriched-quinone thin film is exploited for immobilizing dispersine B, an enzyme. In vitro functional assays demonstrated the dual antibacterial and anti-biofouling resistance properties of the coatings due to the antibacterial effect of silver and the fouling resistance of grafted dispersine B, respectively. Surfaces coated only with silver provide an antibacterial effect but fail to inhibit bacterial attachment, highlighting the usefulness of such dual-action surfaces. The approach presented here provides a simple and effective chemical pathway to construct powerful antibacterial surfaces for various industrial applications.

TiAlN single layer coatings deposited by High-Power Impulse Magnetron Sputtering (HiPIMS) on carbide and Si-wafers substrates were performed. They were characterized in order to study the effects of different process parameters on the film stoichiometry, microstructure and morphology and finally their mechanical and tribological properties were investigated. For comparison, the properties of the same composition Ti50Al50N coatings produced by Cathodic Arc Evaporation (CAE) were also studied. Only the most influential process parameters, which are the effects of duty cycle, pressure, power and bias for the HiPIMS process are here discussed. High-resolution TEM images were used to investigate the microstructure of CAE and HiPIMS coatings and the observations indicate that both processes produced high density Ti50Al50N coatings with a fine fibrous structure, and a similar grain size. XRD analyses showed that TiAlN coatings deposited by CAE and by HiPIMS have a single-phase cubic structure with respectively the (200) and (111) reflection peaks as a preferred orientation. Furthermore, the residual stresses determined by XRD for the HiPIMS coated samples show that it can be possible to tune them from tensile (+500 MPa) to high compressive stresses (−4000 MPa) by adjusting the process parameters. Independently of their intrinsic stress level, the HiPIMS coatings show similar hardness and the values obtained are in the same range of CAE coatings (30–35 GPa) with same composition and thickness. However, during ball-on-disc tests in dry condition using a steel ball against the coated carbide substrate, the behaviour of similar Ti50Al50N as deposited coatings produced by these two processes was different. Lower friction coefficients (−30%) but, higher abrasion kinetic of the steel ball as counterpart during pin-on-disk test (+50%) were recorded for the Ti50Al50N HiPIMS coatings. In conclusion, it is proposed that, for HiPIMS coatings with high compressive stresses (

A coaxial shaped atmospheric pressure plasma torch has been used to deposit the millimetric scale plasma polymer. A detailed experiment has revealed the appearance of three different kinetic regimes with distinct coating morphology: no deposition, circular dot and circular ring formation. The ratio of precursor carrier gas flow to the plasma species carrier gas flow has been identified as crucial factor to separate the three regimes. Further experiments regarding the influence of precursor mass fraction on the dimension and deposition rates has been performed for a circular dot regime to get more insights into the coating shape, size and volume and its relation to gas flow dynamics. A side by side computational fluid dynamic simulation coupled with species transport module has been performed to understand the influence of flow dynamics on coating morphology. The appearance of recirculatory vortices in-between the nozzle and substrate and its role on confinement of precursor at specific region and mixing of plasma species to precursor has been highlighted. A good correlation in between the diameter of thus coated plasma polymer in circular dot regime and the simulated confinement zone is here reported.

UV and visible light photocatalytic composite Pt and Au–TiO2 coatings have been deposited on silicon and glass substrates at low temperature using a hybrid ECWR-PECVD/MS-PVD process. Methylene blue, stearic acid, and sulfamethoxazole were used as dye, organic, and antibiotic model pollutants, respectively, to demonstrate the efficiency of these nanocomposite coatings for water decontamination or self-cleaning surfaces applications. Raman investigations revealed the formation of anatase polymorph of TiO2 in all synthesized coatings with a shifting of the main vibrational mode peak to higher wavenumber in the case of Au–TiO2 coating, indicating an increase number of crystalline defects within this coating. Because of the difference of the chemical potentials of each of the investigated noble metals, the sputtered metal layers exhibit different morphology. Pt sputtered atoms, with high surface adhesion, promote formation of a smooth 2D layer. On the other hand, Au sputtered atoms with higher cohesive forces ...

Atomic force microscopy (AFM) allows high image resolution, based on slight differences in surface height and on imaging transparent structures, thus, is an excellent type of microscopy for imaging nano-sized objects, such as diatoms. Currently and since 1992, the number of publications applying AFM on diatom studies has increased significantly. Our study considers different aspects related with AFM and diatom samples preparation, AFM types and its application in studies of taxonomy, biomineral formation, ultrastructure, mucilage layers, and micromechanical properties. We also present new AFM data highlighting the taxonomical importance of Amphipleura pellucida. From our knowledge, it is the first general review that compiles all the works carried out on Atomic force microscopy (AFM) applied to diatoms, highlighting the AFM advantages regarding the study of these microorganisms as a whole.

A novel atmospheric pressure plasma-initiated chemical vapor deposition (AP-PiCVD) approach toward the growth of conventional polymer layers is characterized and interpreted. A set of three methacrylate monomers (methyl, butyl, and glycidyl methacrylate) were investigated using ultrashort plasma discharges (ca. 100 ns) pulsed at various frequencies, covering a range of duty cycle from 0.1% to 0.000 316%. An unprecedented weight-average molar mass of 94 000 g mol–1 coupled to an outstanding thin film conformality and an excellent chemical functionalities retention was achieved for the best deposition conditions. Insights into the growth mechanisms in AP-PiCVD and their dependence on the monomer’s intrinsic properties are provided.

Due to the undeniable industrial advantages of low-temperature atmospheric-pressure plasma processes, such as low cost, low temperature, easy implementation, and in-line process capabilities, they have become the most promising next-generation candidate system for replacing thermal chemical vapor deposition or wet chemical processes for the deposition of functional coatings. In the work detailed in this article, photocatalytic anatase TiO2 thin films were deposited at a low temperature on polymer optical fibers using an atmospheric-pressure plasma process. This method overcomes the challenge of forming crystalline transition metal oxide coatings on polymer substrates by using a dry and up-scalable method. The careful selection of the plasma source and the titanium precursor, i.e., titanium ethoxide with a short alkoxy group, allowed the deposition of well-adherent, dense, and crystalline TiO2 coatings at low substrate temperature. Raman and XRD investigations showed that the addition of oxygen to the prec...

Temperature sensitive poly(methyl methacrylate) (PMMA) optical fibres were coated with boron doped-anatase crystalline TiO2 thin films in a one-step atmospheric pressure-plasma enhanced chemical vapour deposition (AP-PECVD) process. Both the undoped and interstitial boron-doped TiO2 thin films showed photoactivity under UV irradiation, with the boron-doped thin films presenting higher photodegradation rates when compared to the undoped samples.

Magnetic coatings are used for a lot of applications from data storage in hard discs, spintronics and sensors. Meanwhile, magnetron sputtering is a process largely used in industry for the deposition of thin films. Unfortunately, deposition of magnetic coatings by magnetron sputtering is a difficult task due to the screening effect of the magnetic target lowering the magnetic field strength of the magnet positioned below the target, which is used to generate and trap ions in the vicinity of the target surface to be sputtered. In this work we present an efficient method to obtain soft magnetic thin films by reactive sputtering of a non-magnetic target. The aim is to recover the magnetic properties of Ni after dealloying of Ni and Cr due to the selective reactivity of Cr with the reactive nitrogen species generated during the deposition process. The effects of nitrogen content on the dealloying and DC magnetron sputtering (DCMS) deposition processes are studied here. The different chemical compositions, microstructures and magnetic properties of DCMS thin films obtained by sputtering in reactive gas mixtures with different ratios of Ar/N2 from a non-magnetic Ni-20Cr target have been determined. XPS data indicate that the increase of nitrogen content in the films has a strong influence on the NiCr phase decomposition into Ni and CrN, leading to ferromagnetic coatings due to the Ni phase. XRD results show that the obtained Ni-CrN films consist of a metallic fcc cubic Ni phase mixed with fcc cubic CrN. The lattice parameter decreases with the N2 content and reaches the theoretical value of the pure fcc-Ni, when Cr is mostly removed from the Ni-Cr phase. Dealloying of Cr from a Ni80-Cr20 solid solution is achieved in our experimental conditions and the deposition of Ni ferromagnetic coatings embedding CrN from a non-magnetic target is possible with reactive DC magnetron sputtering.

TiO2 thin films were deposited on polymer substrates (polyethylene terephthalate and polystyrene) at low substrate temperature (

In this work, an atmospheric aerosol assisted pulsed plasma process is reported as an environmentally friendly technique for the preparation of tunable catechol-bearing thin films under solvent and catalyst free conditions. The approach relies on the direct injection of dopamine acrylamide dissolved in 2-hydroxyethylmethacrylate as comonomer into the plasma zone. By adjusting the pulsing of the electrical discharge, the reactive plasma process can be alternatively switch ON (tON) and OFF (tOFF) during different periods of time, thus allowing a facile and fine tuning of the catechol density, morphology and deposition rate of the coating. An optimal tON/tOFF ratio is established, that permits maximizing the catechol content in the deposited film. Finally, a diagram, based on the average energy input into the process, is proposed allowing for easy custom synthesis of layers with specific chemical and physical properties, thus highlighting the utility of the developed dry plasma route.

International audience; The nanostructure and photocatalytic properties of TiO2 thin films deposited by PECVD on silicon substrates were investigated. The films were grown at low temperature (

International audience; This article reports the use of pulsed remote Ar-O 2 microwave plasma assisted chemical vapor deposition with an −NH 2 containing organosilicon precursor ((3-Aminopropyl)triethoxysilane: APTES). It is shown that modifying the plasma pulses duration (t on) and the plasma off duration (t off) allows to finely tune the deposited layer composition. In addition, the results of this work demonstrate that an important film growth occurs during t off , which results in an increased −NH 2 density. Besides, high resolution MALDI-ORBITRAP Mass spectrometry analysis clearly points out that APTES oligomers up to eight base units, including silsesquioxanes (cages), and cyclosi-loxanes (rings) molecules with intact −NH 2 groups are embedded into the as grown pp-APTES thin film. K E Y W O R D S microwave discharges, plasma-enhanced chemical vapour deposition (PECVD), plasma polymerization, pulsed discharges, remote plasma processes

The as-deposited structural properties and the high temperature oxidation mechanisms occurring in Al-Ti-Ta-N and Al-Ti-Ta-Y-N are studied. Yttrium causes structural changes (lattice parameter, texture) depending on the deposition temperature. In oxidised Al-Ti-Ta-Y-N some alumina crystallises in the Ti-rich oxide, because of Y. SIMS shows a transition layer between Al-rich and Ti-rich oxides and a shallow unoxidized Ti-rich region at the interface with the nitride in both materials, not reported before, explained with SIMS of isotopically oxidised samples. The main effect of Y on Al-Ti-Ta-N is decreasing the kinetics of formation of alumina, making it more uniformly spread and protective.

Liquid-assisted plasma-enhanced chemical vapor deposition (LA-PECVD) provides a convenient approach toward the preparation of functional surfaces. In this work, the LA-PECVD approach is reported for the high deposition rate of tuneable catechol and quinone-functionalized coatings from plasma polymerization of vinyltrimethoxysilane (VTMOS) and dopamine acrylamide (DOA). Most particularly, the influence of the liquid precursor delivery rate and of the plasma power density on the chemistry and morphology of the formed layers are investigated. Precursor delivery rate and plasma power conditions are found, through mass measurement, XPS, FTIR, and Raman spectroscopy, to enable the high deposition rate of cross-linked coatings. Interestingly, the integration and conservation of the catechol functional group from the DOA monomer are highlighted through the reduction of a silver nitrate solution and silver nanoparticles formation observation via SEM/EDX. Due to the presence of oxidant species and to the bombardment of the layer with highly energetic species, quinone groups formation is likely to occur during the plasma treatment and is then highlighted via ToF-SIMS analyses of a surface successfully derivatized with a β-lactamase. The conservation of both functional groups on the surface makes this type of layer promising for numerous applications. Quinone groups provide a real platform for the immobilization of biomolecules with various properties, e.g., antibiotics degradation, antibacterial, while the catechol groups are interesting for trapping radicals or metal ions for water treatment applications.

From results of in situ FTIR absorption and optical emission spectroscopy, the interaction of (3-aminopropyl)triethoxysilane (APTES) with late ArN2 afterglow is shown to occur mainly with N atoms. They react preferentially with carbon from CHx groups in the precursor, leading to the synthesis of CN bonds. No production of NH radical is observed, demonstrating the lack of direct reaction between active nitrogen and APTES. The NH2 group is not affected by the afterglow. One of the CC bonds of the propylamine group in the APTES is likely broken. These nanoparticles present secondary amides due to reactions with active nitrogen. They are amorphous and react in air to produce a salt.

The deposition of polymeric thin layers bearing reactive functional groups is a promising solution to provide functionality on otherwise inert surfaces, for instance, for bioconjugation purposes. Atmospheric pressure plasma (AP plasma) deposition technology offers many advantages, such as fast deposition rates, low costs, low waste generation and suitability for coating various kind of material surfaces. In this work, the AP plasma-assisted copolymerization of methyl methacrylate (MMA) with a vinyl derivative of L-DOPA was studied in order to deposit coatings with reactive catechol/quinone groups suitable for protein covalent immobilization. The effect of adding a chemical cross-linker, between 0 and 2 mol%, to the monomer mixture is also studied in order to prepare robust plasma PMMA-based layers in liquid physiological media. The layer prepared with 0.2 mol% of cross-linker shows the best balance between stability in saline-buffered media and surface functionalization. Bioconjugation via the grafting of Ranaspumin-2 recombinant, a naturally occurring surfactant protein, is carried out in a single step after plasma deposition. Protein immobilization is corroborated by Quartz Crystal Microbalance with Dissipation (QCM-D) and Surface Plasmon Resonance (SPR) analyses and confirmed via Epicocconone staining, X-Ray Photoemission Spectroscopy (XPS) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) measurements and surface wettability characterizations. The bio-functionalized layers presented an enhanced activity against the adhesion of Human Serum Albumin (HSA), indicating the grafting potential of the Ranaspumin-2 bio-surfactant to produce anti-biofouling functional coatings.

Transparent anti-fogging and self-cleaning coatings are of great interest for many applications, including solar panels, windshields and displays or lenses to be used in humid environments. In this paper, we report on the simultaneous synthesis, at atmospheric pressure, of anatase TiO2 nanoparticles and low-temperature, high-rate deposition of anatase TiO2/SiO2 nanocomposite coatings. These coatings exhibit durable super-hydrophilic and photocatalytic properties. The strategy followed relies on concomitant and separated injections of titania, i.e. titanium isopropoxide, and silica, i.e. hexamethyldisiloxane, precursors in the stream of a blown-arc discharge to form transparent anti-fogging and self-cleaning anatase TiO2/SiO2 nanocomposite coatings on polymer substrates.

In this work, an atmospheric-pressure dielectric barrier discharge process is exploited for the fast deposition of adherent epoxy-rich layers acting as a versatile platform for the efficient one-step biomolecule immobilization in mild aqueous conditions. Particular attention is given to the influence of the plasma process parameters on the chemical and morphological properties of the deposited layers and on their subsequent exploitation for chemical interfacial reactions. As a proof-of-concept, two enzymes with drastically different biological properties, namely dispersin B and a laccase, are immobilized onto functionalized metallic surfaces. The pH of the enzyme solution appears as a key parameter to control the amount of immobilized enzyme on the plasma functionalized surfaces, thus leading to bioactive surfaces with improved stability and activity.

The accumulation of crystallization deposits at the surface of heat exchangers results in the increase of the heat transfer resistance and a drastic loss of efficiency. Coating surfaces with a thin film can limit the scale-surface adhesion force and thus the fouling process. This study compares the efficiency of TiO2 layers exhibiting various crystalline planes and microstructures to reduce the kinetic of fouling. Molecular modelling with density functional theory is first carried out to determine the energy of CaCO3 deposition on anatase (1 0 1), (0 0 4), and (2 0 0) surfaces as well as on a rutile (1 0 1) one. TiO2 thin films (thickness

Atmospheric plasma deposition of DiEthylAllyl Phosphate (DEAP) has been performed to study the behaviour of an allylic phosphate-based monomer in a nitrogen Atmospheric Pressure-Dielectric Barrier Discharge (AP-DBD). The deposition kinetics and chemical structures of the different coatings have been studied as a function of the duty cycle and the power dissipated in the discharge. It has been highlighted that it is possible to obtain different chemistries, from organic coatings in which the monomer structure is remaining to inorganic polyphosphate-based ones. Different mechanisms of deposition have been outlined and discussed taking into account the deposition kinetics, the coatings chemistries and the monomer reactivity in the gas phase.

International audience; He/N-2 cold atmospheric plasma treatment of E. coli suspension leads to a fast and efficient inactivation process. Significant generation of ammonium is reported. The formation of NH4+ species in saline solution treated by cold atmospheric plasma is proposed for the first time as the main process responsible for the fast bacterial inactivation in pH-buffered solutions, at ambient temperature and physiological pH.

Bioconjugation of enzymes on coatings based on polydopamine (PDA) layers is an appealing approach to control biological responses on biomedical implant surfaces. As alternative to PDA wet deposition, a fast, solvent-free, and dynamic deposition approach based on atmospheric-pressure plasma dielectric barrier discharge process is considered to deposit on metallic surfaces acrylic-based interlayers containing highly chemically reactive catechol/quinone groups. A biomimetic approach based on covalent immobilization of Dispersin B, an enzyme with antibiofilm properties, shows the bioconjugation potential of the novel plasma polymer layers. The excellent antibiofilm activity against Staphylococcus epidermidis is comparable to the PDA-based layers prepared by wet chemical methods with slow deposition rates. A study of preosteoblastic MG-63 human cell line viability and adhesion properties on plasma polymer layers demonstrates early interaction required for biomedical applications.

Due to the undeniable industrial advantages of low-temperature atmospheric-pressure plasma processes, such as low cost, low temperature, easy implementation, and in-line process capabilities, they have become the most promising next-generation candidate system for replacing thermal chemical vapor deposition or wet chemical processes for the deposition of functional coatings. In the work detailed in this article, photocatalytic anatase TiO

A density functional theory (PBE functional) investigation is carried out, in which a model of an amorphous silica surface is functionalized by ortho-benzoquinone. Surface functionalization with catechol and quinone-based compounds is relevant in biomedical fields, from prosthetic implants to dentistry, to develop multifunctional coatings with antimicrobial properties. The present study provides atomistic information on the specific interactions between the functionalizing agent and the silanol groups at the silica surface. The distinct configurations of the functional groups, the hydrogen bond pattern, the role of dispersion forces and the simulated IR spectra provide detailed insight into the features of this model surface coating. Ab initio molecular dynamics gives further insights into the mobility of the functionalizing groups. As a final step, we studied the condensation reaction with allylamine, via Schiff base formation, to ground subsequent simulations on condensation with model peptides of antimicrobial activity.

On-line atmospheric pressure plasma treatment of cylindrical substrates is of great interest in tire industry in view of developing a cheaper and cleaner process than electrolytic plating ones that are applied on metallic tire reinforcing materials. Here we assess the feasibility of such a continuous treatment by depositing organo-chlorinated thin films from dichloromethane on zinc-plated steel wires crossing a tubular dielectric barrier discharge. We show that working conditions highly influence layers growth and have to be carefully adjusted for obtaining homogeneous and defect-free coatings. Thin films chemistry is strongly dependent on the energy injected in the discharge. Layers become more inorganic when power increases, resembling carbon black or graphite and no longer hydrocarbon.

AlTiTaN coatings have been demonstrated to have high thermal stability at temperatures up to 900 °C. It has been speculated that the high oxidation resistance promotes an improved wear resistance, specifically for dry machining applications. This work reports on the influence of temperature up to 900 °C on the wear mechanisms of AlTiTaN hard coatings. DC magnetron-sputtered coatings were obtained from an Al(46)Ti(42)Ta(12) target, keeping the substrate bias at -100 V and the substrate temperature at 265 °C. The coatings exhibited a single-phase face-centered cubic AlTiTaN structure. The dry sliding tests revealed predominant abrasion and tribo-oxidation as wear mechanisms, depending on the wear debris formed. At room temperature, abrasion leading to surface polishing was observed. At 700 and 800 °C, slow tribo-oxidation and an amorphous oxide formed reduced the wear rate of the coating compared to room temperature. Further, an increase in temperature to 900 °C increased the wear rate significantly due to fast tribo-oxidation accompanied by grooving. The friction coefficient was found to decrease with temperature increasing from 700 to 900 °C due to the formation of oxide scales, which reduce adhesion of asperity contacts. A relationship between the oxidation and wear mechanisms was established using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, surface profilometry, confocal microscopy, and dynamic secondary ion mass spectrometry.

A simple, efficient and scalable method for the atmospheric pressure plasma initiated chemical vapor deposition of conventional polymer is demonstrated. Ultra-short square pulse dielectric barrier discharge, which allows high deposition rates even for plasma duty cycle as low as 0.01%, is used to deposit a glycidyl methacrylate (GMA) polymer layer. The polymer structure of the thin films is evidenced by matrix-assisted laser desorption/ionization high-resolution mass spectrometry. Polymer molecular weights up to 30 000 g mol−1 are found by size exclusion chromatography (SEC), highlighting the suitability of the plasma initiated CVD method for the deposition of polymer layers.

Herein, plasma deposited thermally responsive thin polymer films from N-vinylcaprolactam (NVCL) is reported for the first time by using a low pressure RF plasma process. While FT-IR and XPS analyses highlight the film chemistry, ToF-SIMS combined with MALDI-MS analyses allow to accurately identify different oligomer distributions in the deposited film. The switching behavior of these smart surfaces is confirmed with water contact angle measurements at low and high temperatures, allowing also to estimate the Lower Critical Solution Temperature.