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Solid-state dewetting (SSD) on patterned substrates is a straightforward method for fabricating ordered arrays of metallic nanoparticles on surfaces. However, a drawback of this procedure is that the patterning of substrates usually requires time-consuming and expensive two-dimensional (2D) fabrication methods. Nanostructured thin films deposited by oblique angle deposition (OAD) present at the surface a form of stochastically arranged periodic bundles of nanocolumns that might act as a patterned template for fabricating arrays of nanoparticles by SSD. In this work, we explore this concept and investigate the effect of three different types of OAD SiO2 thin films on the SSD of Au deposited on their surface. We demonstrate that the size and spatial distribution of the particles can be tailored through the surface morphology of these OAD film substrates. It has been found that the SSD of the evaporated Au layer gives rise to a bimodal size distribution of particles. A majority of them appeared as mesoparticles with sizes ≳100 nm and the rest as nanoparticles with ∼10 nm, respectively, located either on top of the nanocolumns following their lateral distribution (i.e., resulting from a patterning effect) or incorporated inside the open mesopores existing among them. Moreover, on the SiO2-OAD thin films where interconnected nanocolumnar bundles arrange in the form of discrete motifs, the patterning effect gave rise to the formation of approximately one Au mesoparticle per motif, which is one of the assets of patterned SSD. The morphological, optical (i.e., plasmon resonance), and crystalline structural characteristics of Au mesoparticles suggest that the interplay between a discontinuous nanocolumnar surface acting as a template and the poor adhesion of Au onto SiO2 are key factors for the observed template effect controlling the SSD on the surface of OAD thin films.

Herein, we present the development of supported organic nanofabrics formed by a conformal polymer-like interconnection of small-molecule organic nanowires and nanotrees. These organic nanostructures are fabricated by a combination of vacuum and plasma-assisted deposition techniques to generate step by step, single-crystalline organic nanowires forming one-dimensional building blocks, organic nanotrees applied as three-dimensional templates, and the polymer-like shell that produces the final fabric. The complete procedure is carried out at low temperatures and is compatible with an ample variety of substrates (polymers, metal, ceramics; either planar or in the form of meshes) yielding flexible and low solid-fraction three-dimensional nanostructures. The systematic investigation of this progressively complex organic nanomaterial delivers key clues relating their wetting, nonwetting, and anti-icing properties with their specific morphology and outer surface composition. Water contact angles higher than 150° are attainable as a function of the nanofabric shell thickness with outstanding freezing-delay times (FDT) longer than 2 h at −5 °C. The role of the extremely low roughness of the shell surface is settled as a critical feature for such an achievement. In addition, the characteristic interconnected microstructure of the nanofabrics is demonstrated as ideal for the fabrication of slippery liquid-infused porous surfaces (SLIPS). We present the straightforward deposition of the nanofabric on laser patterns and the knowledge of how this approach provides SLIPS with FDTs longer than 5 h at −5 °C and 1 h at −15 °C., We thank the AEI, MINECO (MAT2016-79866-R), and Consejerıa de Economia y Conocimiento de la Junta de Andalucia (US-1263142), the EU through cohesion fund and FEDER 20014-2020 programs and H2020 Phobic2Ice project(ref 690819) for financial support. This project has received funding from the EU-H2020 research and innovation program under the grant agreement No. 654360 (Id285) having benefitted from the access provided by CEA-Leti in Grenoble (France) within the framework of the NFFA-Europe Transnational Access Activity. F.J.A. and J.R.S.-V. acknowledge the Juan de la Cierva and Ramon y Cajal Programs, respectively. C.L.-S. and J.R.S.-V. thank the University of Seville through the VI PPIT-US.

Laser ablation is an effective method to clean Cu-based alloys. A novel procedure of characterisation was developed involving O isotopes evaluated by ToF-SIMS spectroscopy to assess the driving mechanisms of laser-surface interactions. The presence of re-oxidised compounds was detected, discerning between the oxygen from the corrosion layer and the one introduced by the interaction with the laser (that was generated in a controlled atmosphere of O diluted in N). A set of samples treated with different laser conditions were characterised by FESEM and μRaman. The results have shown that re-oxidation phenomenon can occur and its selectivity depends on the laser conditions., Dr. R. Lahoz wishes to acknowledge professional support of the CSIC Interdisciplinary Thematic Platform “Open Heritage: Research and Society (PTI-PAIS)”. Dr. E. Di Francia would like to acknowledge the European Federation of Corrosion (EFC) – EUROCORR Young Scientist Grant Selection Committee 2016 that stimulated the initial collaboration that subsequently produced this research. Dr. V. Rico thanks the FEDER program through AEI-MICINN (PID2019-110430GB-C21) and Junta de Andalucía (PAIDI-2020 through project P18-RT-3480) for financial support.

Identification of hydrocarbons and crude oils is typically carried out with samples that, taken from natural sources or refineries, must be brought to the laboratory for their analysis with rather sophisticated instruments. Alternatively, “in situ” procedures have been also developed for this purpose. In this work, we propose the use of a series of several sensor systems based on photonic transducers in the form of chips for the identification and classification of crude oils and hydrocarbons through the determination of their refractive index in the visible and absorption in the near infrared regions of the electromagnetic spectrum. Two of the photonic transducers rely on modifications of a Bragg microcavity and they monitor the changes in visible light interference phenomena that occur in response to the variation of the refractive index of oils. The third one, in the form of a dielectric mirror, monitors the near infrared absorption of crude oils and hydrocarbons through the recording of a transflectance spectrum. The capacity of these transducers for crude oil identification is proved by the analysis of a series of oils and distilled fractions that have been properly identified and classified as a function of their density and partition of long hydrocarbon chains. The three photonic transducers are operated with optical fibers and can be used in static and dynamic modes, this latter under conditions that are especially well-suited for “insitu” analysis of oil streams in real facilities. The proved resistance of the chips to high pressure and temperature conditions supports their suitability to withstand harsh working environments as those existing in extraction wells.

DOI: 10.1016/j.apmt.2020.100815 Infusion of low surface tension liquids in nanostructured surfaces is currently used to promote an anti-icing response, although the long term stability of these systems is often jeopardized by losses of the infused liquid. In this work, we propose an alternative to the infusion procedure to induce a more effective and long lasting anti-icing capacity. The method consists of a combination of surface nanostructuration with the chemical grafting of fluorocarbon molecules. Al6061 substrates have been subjected to laser roughening and further modified with a nanostructured Al2O3 thin film to achieve a dual roughness and porous surface state. These surfaces have been subjected to a grafting treatment with perfluorooctyltriethoxysilane (PFOTES) vapor or, for comparative purposes, infused with a low surface tension liquid. A comparative analysis of the wetting, water condensation and anti-icing properties of these two systems showed an outstandingly better performance for the grafted surfaces with respect to the infused ones. Grafted surfaces were markedly superhydrophobic and required higher water vapor pressures to induce condensation. When looking for their anti-icing capacity, they presented quite long freezing delay times for supercooled water droplets (i.e. almost four hours) and exhibited a notably low ice accretion in a wind tunnel test. The high aging resistance and durability of these grafted surfaces and the reproducibility of the results obtained when subjected to successive ice accretion cycles show that molecular grafting is an efficient anti-icing methodology that, in aggressive media, may outperform the classical infusion procedures. The role of the fluorocarbon chains anchored on the surface in inducing an anti-icing functionality is discussed. This work has been carried out with the support of the EU project PHOBIC2ICE (ref 690819). The authors want to specially thank Airbus Group Innovations DE, Concordia Institute of Aerospace Design & Innovation of Concordia University and Department of Engineering Physics of Polytechnique Montreal for, respectively, the rain erosion, thermal cycling and sand erosion tests carried out within the frame of this project. The authors also thank the European Regional Development Funds program (EU-FEDER) and the MINECO-AEI (MAT2016-79866-R, PID2019-109603RA-I00, PID2019-110430GB-C21 and CSIC 201860E050) for financial support. CLS thanks the University of Seville through the VI “Plan Propio de Investigación y Transferencia de la US” (VI PPIT-US). This work has been carried out with the support of the EU project PHOBIC2ICE (ref 690819). The authors want to specially thank Airbus Group Innovations DE, Concordia Institute of Aerospace Design & Innovation of Concordia University and Department of Engineering Physics of Polytechnique Montreal for, respectively, the rain erosion, thermal cycling and sand erosion tests carried out within the frame of this project. The authors also thank the European Regional Development Funds program (EU-FEDER) and the MINECO-AEI (MAT2016-79866-R, PID2019-109603RA-I00, PID2019-110430GB-C21 and CSIC 201860E050) for financial support. CLS thanks the University of Seville through the VI Plan Propio de Investigación y Transferencia With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)

Due to their outstanding physical and mechanical features, ZrN thin films are increasingly used as coatings to protect materials intended for nuclear applications such as Zirconium. To our knowledge, there is no report of pulsed laser deposition (PLD) of ZrN thin films on a Zr substrate. In this work, we have successfully prepared ZrN thin films on Zr substrates using the PLD technique with a KrF excimer laser, in a N2 environment at 2 Pa pressure and a fixed substrate temperature of 500 °C. The deposited 200 nm ZrN thin films exhibited a homogeneous surface and showed a face-centered cubic polycrystalline structure. The surface roughness was 3.69 nm. X-ray diffraction, Raman and X-ray photoelectron spectroscopy measurements confirmed the presence of ZrN. The coated sample's mean value of hardness (11.6 GP) doubled that of the uncoated sample.

One-dimensional (1D) nanostructured surfaces based on high-density arrays of nanowires and nanotubes of photoactive titanium dioxide (TiO2) present a tunable wetting behavior from superhydrophobic to superhydrophilic states. These situations are depicted in a reversible way by simply irradiating with ultraviolet light (superhydrophobic to superhydrophilic) and storage in dark. In this article, we combine in situ environmental scanning electron microscopy (ESEM) and near ambient pressure photoemission analysis (NAPP) to understand this transition. These experiments reveal complementary information at microscopic and atomic level reflecting the surface wettability and chemical state modifications experienced by these 1D surfaces upon irradiation. We pay special attention to the role of the water condensation mechanisms and try to elucidate the relationship between apparent water contact angles of sessile drops under ambient conditions at the macroscale with the formation of droplets by water condensation at low temperature and increasing humidity on the nanotubes' surfaces. Thus, for the as-grown nanotubes, we reveal a metastable and superhydrophobic Cassie state for sessile drops that tunes toward water dropwise condensation at the microscale compatible with a partial hydrophobic Wenzel state. For the UV-irradiated surfaces, a filmwise wetting behavior is observed for both condensed water and sessile droplets. NAPP analyses show a hydroxyl accumulation on the as-grown nanotubes surfaces during the exposure to water condensation conditions, whereas the water filmwise condensation on a previously hydroxyl enriched surface is proved for the superhydrophilic counterpart., We thank the Junta de Andalucia (TEP8067, FQM-196, and P12-FQM-2265), the European Regional Development Funds program (EU-FEDER), and the AEI and MINECO (projects MAT2013-40852-R, MAT2013-42900-P, MINECO-CSIC 201560E055, and MAT2016-79866-R) for financial support

Based on an already tested laboratory procedure, a new magnetron sputtering methodology to simultaneously coat two-sides of large area implants (up to ~15 cm2) with Ti nanocolumns in industrial reactors has been developed. By analyzing the required growth conditions in a laboratory setup, a new geometry and methodology have been proposed and tested in a semi-industrial scale reactor. A bone plate (DePuy Synthes) and a pseudo-rectangular bone plate extracted from a patient were coated following the new methodology, obtaining that their osteoblast proliferation efficiency and antibacterial functionality were equivalent to the coatings grown in the laboratory reactor on small areas. In particular, two kinds of experiments were performed: Analysis of bacterial adhesion and biofilm formation, and osteoblasts–bacteria competitive in vitro growth scenarios. In all these cases, the coatings show an opposite behavior toward osteoblast and bacterial proliferation, demonstrating that the proposed methodology represents a valid approach for industrial production and practical application of nanostructured titanium coatings., The authors acknowledge the financial support from the European Regional Development Funds program (EU-FEDER) and the MINECO-AEI (201560E055, MAT2014-59772-C2-1-P, MAT2016-75611-R, and MAT2016-79866-R and network MAT2015-69035-REDC). The authors also thank the University of Seville (V and VI PPIT-US) and Fundación Domingo Martínez for financial support. M.V.-R. also thanks the European Research Council (advanced grant VERDI; ERC-2015-AdG proposal 694160). The authors thank the MiNa Laboratory at IMN funded by CM (S2018/NMT-4291 TEC2SPACE), MINECO (CSIC13-4E-1794), and the EU (FEDER, FSE) for the support.

7 pags., 6 figs., 1 app., A radial polarization converter is a super-structured optical retarder that converts a conventional linearly polarized light beam into a structured beam with radial or azimuthal polarization. We present a new type of these sophisticated optical elements, which is made of porous nanostructured sculptured single thin films or multilayers prepared by physical vapor deposition at an oblique angle. They are bestowed with an axisymmetric retardation activity (with the fast axis in a radial configuration). In particular, a Bragg microcavity multilayer that exhibits a tunable transmission peak in the visible range with a retardance of up to 0.35 rad has been fabricated using this methodology. Owing to the highly porous structure of this type of thin films and multilayers, their retardance could be switched off by liquid infiltration. These results prove the possibility of developing wavelength dependent (through multilayer optical design) and switchable (through vapor condensation or liquid infiltration within the pore structure) radial polarization converters by means of oblique angle physical vapor deposition., We acknowledge the support of the European Regional Development Funds program (EU-FEDER), the Spanish MinistryEconomy, Industry, and Competitiveness (projects 201560E055,MAT2016-79866-R, RECUPERA 2020 and Red CONSOLIDER MAT2015-69035-REDC).

Traditionally porous silicon based photonic structures have been prepared by electrochemically etching of silicon. In this work, porous multilayers of nanocolumnar SiOx and SiO2 thin films acting as near infrared (NIR) 1D-photonic nanostructures are prepared by magnetron sputtering deposition at oblique angles (MS-OA). Simultaneous control of porosity and stoichiometry of the stacked films is achieved by adjusting the deposition angle and oxygen partial pressure according to a parametric formula. This new methodologoy is proved for the synthesis of SiOx thin films with x close to 0.4, 0.8, 1.2, 1.6 and nanostructures varying from compact (at 0° deposition angle) to highly porous and nanocolumnar (at 70° and 85° deposition angles). The strict control of composition, structure and nanostructure provided by this technique permits a fine tuning of the absorption edge and refraction index at 1500 nm of the porous films and their manufacturing in the form of SiOx-SiO2 porous multilayers acting as near infrared (NIR) 1D-photonic structures with well-defined optofluidic responses. Liquid tunable NIR Bragg mirrors and Bragg microcavities for liquid sensing applications are presented as proof of concept of the possibilities of this MS-OA manufacturing method as an alternative to the conventional electrochemical fabrication of silicon based photonic structures.

7 pags., 5 figs., Unlike topography patterning, widely used for numerous applications and produced by means of different technologies, there are no simple procedures to achieve surface compositional patterning at nanometric scales. In this work we have developed a simple method for 2D patterning the composition of thin films. The method relies on the magnetron sputtering deposition at oblique angles onto patterned substrates made by laser induced periodic surface structures (LIPSS). The method feasibility has been demonstrated by depositing SiOx thin films onto LIPSS structures generated in Cr layers. A heterogeneous and aligned distribution of O/Si ratios (and different Sin+ chemical states) along the LIPSS structure in length scales of some hundreds nm's has been proven by angle resolved X-ray photoelectron spectroscopy and a patterned arrangement of composition monitored by atomic force microscopy-Raman analysis. The obtained results are explained by the predictions of a Monte Carlo simulation of this deposition process and open the way for the tailored one-step fabrication of surface devices with patterned compositions., The authors thank the European Regional Development Fund program (EU-FEDER) and the MINEICO-AEI (201560E055, MAT2016-79866-R, TEC2017-82464-R projects and network MAT2015-69035-REDC) for financial support. We also acknowledge the support of the University of Seville (V and VI PPIT-US).

This paper reports a new methodology for the coloring of glazed ceramic tiles consisting of the near infrared pulsed laser processing of copper containing oxide coatings prepared by magnetron sputtering. As a second approach, the employ for the same purpose of a novel laser furnace technique is also described. Changing the laser parameters and using the laser furnace to treat the tiles at high temperature during irradiation has resulted in a wide color palette. The optical characterization of the modified tiles by UV‐Vis spectroscopy has been complemented with their microstructural and compositional analysis by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Time Of Flight Secondary Ion Mass Spectrometry (TOF‐SIMS). The chemical composition of the surface was obtained by X‐ray Photoemission Spectroscopy (XPS) and its structure determined by X?ray diffraction (XRD). The chemical resistance was characterized by several tests following the norm ISO 10545‐13. Color changes have been attributed to surface microstructural and chemical transformations that have been accounted for by simple models involving different ablation, melting, diffusion, and segregation/agglomeration phenomena depending on the laser treatments employed., Financial support from the EU (LIFE11/ENV/ES560), Innovaragón (ITA‐DGA/ES 1368), DGA (Group T87), and projects 201560E055, MAT2015‐69035‐REDC and MAT2016‐79866‐R from MINECO are gratefully acknowledged. F. Rey‐García acknowledges the Portuguese Science and Technology Foundation (FCT) for the Grant SFRH/BPD/108581/2015.

Until recently, superhydrophobicity was considered as a hint to predict surface icephobicity, an association of concepts that is by no means universal and that has been proven to depend on different experimental factors and material properties, including the actual morphology and chemical state of surfaces. This work presents a systematic study of the wetting and freezing properties of aluminum Al6061, a common material widely used in aviation, after being subjected to nanosecond pulsed IR laser treatments to modify its surface roughness and morphology. All treated samples, independent of their surface finishing state, presented initially an unstable hydrophilic wetting behavior that naturally evolved with time to reach hydrophobicity or even superhydrophobicity. To stabilize the surface state and to bestow the samples with a permanent and stable hydrophobic character, laser-treated surfaces were covered with a thin layer of CFx prepared by plasma-enhanced chemical vapor deposition. A systematic comparison between freezing delay (FD) and wetting properties of water droplets onto these plasma-/polymer-modified laser-treated surfaces that, under conditions where a heterogeneous nucleation mechanism prevails, surface morphology rather than the actual value of the surface roughness parameter the key feature for long FD times. In particular, it is found that surface morphologies rendering a Cassie–Baxter wetting regime longer FDs than those characterized by a Wenzel-like wetting state. It is that laser treatment, with or without additional coverage with thin CFx coatings, affects wetting and ice formation behaviors and might be an efficient procedure to mitigate icing problems on metal surfaces., This work has been carried out with the support of the EU project PHOBIC2ICE (ref 690819). The authors also thank the European Regional Development Funds program (EU-FEDER) and the MINECO-AEI (201560E055 and MAT2016-79866-R and network MAT2015-69035-REDC) for financial support.

This paper presents a new method for the fabrication of metal-like decorative layers on glazed ceramic tiles. It consists of the laser treatment of copper thin films prepared by electron beam evaporation at glancing angles. A thin film of discontinuous copper nanoparticles was electron beam evaporated in an oblique angle configuration onto ceramic tiles and an ample palette of colors obtained by laser treatment both in air and in vacuum. Scanning electron microscopy (SEM and FESEM) along with UV-vis-NIR spectroscopy and time of flight secondary ion mass spectrometry (TOF-SIMS) analysis were used to characterize the differently colored layers. Based on these analyses, color development has been accounted for by a simple model considering surface melting phenomena and different microstructural and chemical transformations of the outmost surface layers of samples., Financial support from the EU (Grant LIFE11/ENV/ES560), Innovaragon (Grant ITA-DGA/ES 1368), DGA (Group T87), MINECO (Projects MAT2013-40852-R and MAT2013-42900-P), and Junta de Andalucia (Projects TEP 8067 and FQM 6900) is gratefully acknowledged. F.R.-G. acknowledges the Portuguese Science and Technology Foundation for Grant SFRH/BPD/108581/2015.

This work describes an in-situ Nd:YAG laser-assisted coating method to modify industrial glazed ceramic surfaces. The method makes use of a Cu polymer coordination complex, transformed via 1064 nm continuos wave (cw) laser irradiation, into a lustre-type glassy coating covering the ceramic substrate. The obtained coatings, with typical thicknesses ranging between 4 and 14 μm, become integrated onto the ceramic glaze via a sharp interface, as found by SEM observation. Diffuse Reflectance UV-vis spectroscopy shows that the lustre effect arises from surface plasmon resonant effects associated to the formation of nanometric size Cu particles dispersed throughout the glaze coating. This was confirmed by XPS analysis and other techniques showing that the laser decomposition treatment induces the redox transformation of the Cu (II) complexes, present in the original precursor, into reduced Cu (0) nanoparticles., Financial support from the EU (LIFE11/ENV/ES560), Innovaragón (ITA-DGA/ES 1368), DGA (Group T87), and projects MAT2013-40852-R and MAT2013- 42900-P from MINECO and TEP 8067 and FQM 6900 from the Junta de Andalucía is greatfully acknowledged.

The authors thank the Junta de Andalucia (P12-FQM-2265) and the Spanish Ministry of Economy and Competitiveness (Projects MAT2013-42900-P, MAT2013-40852-R, MINECO-CSIC 201560E055) for financial support.

Target poisoning in reactive magnetron sputtering deposition of thin films is an undesired phenomenon, well known for causing a drastic fall of the process efficiency. We demonstrate that when this technique is operated at oblique angles, films with composition raging from pure metallic to stoichiometric compound can be grown in non-poisoned conditions, thus avoiding most of the associated drawbacks. We have employed amorphous TiOx, although the presented results can be easily extrapolated to other materials and conditions. It is found that the proposed method improves 400% the growth rate of TiO2 thin films.

This work presents a novel bilayer Ni/Cu porous nanostructured film electrode prepared by physical vapor deposition (PVD) in an oblique angle configuration. Scanning electron microscopy (SEM) data revealed that the film, with an approximate thickness of 200 nm, is formed by tilted nanocolumns of around 50 nm of diameter and an inclination of 30° with respect to the surface normal. X ray photoelectron spectroscopy (XPS) data confirmed a bilayer configuration with Cu and Ni located at the top and bottom parts of the film, respectively. A porosity of ca. 45-35% as determined by Rutherford back scattering (RBS) offered a large exposed area and excellent diffusion properties that, combined with a very good catalytic activity, rendered these films excellent electrodes for the quantitative determination of glucose. Under optimized working conditions of detection these electrodes presented a high sensitivity of 2.53 A M cm (R: 0.999), a limit of detection of 0.23 μM and a time response of ca. 2 s. The sensors did not show any loss of response during a period of 4 months. The selectivity of the sensor was checked against various interferences, including physiological compounds, different sugars and ethanol, in all cases with excellent results. The feasibility of using of this sensor for practical applications was confirmed by successfully determining the glucose content in different commercial beverages., The funds for the development of the present work have been provided by the MINECO and the “Fondo social Europeo”, (project RECUPERA 2020) and projects MAT2013-40852-R and MAT2013-42900-P from MINECO and TEP 8067 and FQM 6900 from the Junta de Andalucía. MINECO/ICTI2013-2016/MAT2013-42900-P

Nickel nanoporous thin films deposited on Indium tin oxide conductive plates have been prepared by physical vapor deposition in an oblique angle configuration. The scanning electron microscopy characterization of these films revealed a microstructure formed by tilted nanocolumns of ca. 40-60 nm of diameter inclined by ca. 26° with respect to the normal. These highly porous films had ca. 30% of void space and provided a large exposed area and outstanding diffusion properties for sensor applications.X-ray diffraction analysis confirmed the deposition ofmetallic nickel, while Raman and X-ray photoelectron spectroscopies demonstrated that electrochemically treated films presented an oxi/hydroxide outer layer that is the active phase for glucose sensing. The activated electrodes had a high sensitivity (2.05 A M cm), an excellent coefficient of determination (R: 0.999), an outstanding reproducibility (3.2%) and a detection limit of 0.34 μM. Their glucose selectivity was excellent with regard to common electroactive interferences and other sugars found in agro-alimentary products. Tests carried out with commercial beverages proved the reliability of these electrodes for glucose analysis in real conditions.

The nano-porosity embedded into the tilted and separated nanocolumns characteristic of the microstructure of evaporated thin films at oblique angles has been critically assessed by various variants of the positron annihilation spectroscopy. This technique represents a powerful tool for the analysis of porosity, defects and internal interfaces of materials, and has been applied to different as-deposited SiO2 and TiO2 thin films as well as SiO2/TiO2 multilayers prepared by electron beam evaporation at 70° and 85° zenithal angles. It is shown that, under same deposition conditions, the concentration of internal nano-pores in SiO2 is higher than in TiO2 nanocolumns, while the situation is closer to this latter in TiO2/SiO2 multilayers. These features have been compared with the predictions of a Monte Carlo simulation of the film growth and explained by considering the influence of the chemical composition on the growth mechanism and, ultimately, on the structure of the films.

In this work we investigate by in-situ near-ambient pressure photoemission (NAPP) spectroscopy the phenomenon of Electrochemical Promotion of Catalysis (EPOC). We studied the reduction and diffusion kinetics of alkaline ions in a solid electrolyte cell formed by a nickel electrode supported on K+-β-alumina electrolyte. Experiments in ultra-high vacuum and in the presence of steam showed that the amount of potassium atoms supplied to the surface is probably affected by nickel electronic modifications induced by adsorbed OH− groups. It was also deduced that part of the segregated potassium would be adsorbed at inner interfaces where it would be inaccessible to the photoelectron analyzer. A migration mechanism of the promoter is proposed consisting in: (i) the electrochemical reduction of the alkali ions (potassium) at the Ni/solid electrolyte/gas interface; (ii) the spillover of potassium atoms onto the Ni gas-exposed surface; and (iii) the diffusion of potassium atoms to Ni inner grain boundary interfaces., En este trabajo investigamos mediante espectroscopía de fotoemisión a presión cercana al ambiente in situ (NAPP) el fenómeno de la Promoción Electroquímica de la Catálisis (EPOC). Estudiamos la cinética de reducción y difusión de iones alcalinos en una celda de electrolito sólido formada por un electrodo de níquel soportado sobre electrolito K + -β-alúmina. Los experimentos en vacío ultraalto y en presencia de vapor mostraron que la cantidad de átomos de potasio suministrados a la superficie probablemente se ve afectada por modificaciones electrónicas de níquel inducidas por OH adsorbido .grupos También se dedujo que parte del potasio segregado sería adsorbido en las interfaces internas donde sería inaccesible para el analizador de fotoelectrones. Se propone un mecanismo de migración del promotor que consiste en: (i) la reducción electroquímica de los iones alcalinos (potasio) en la interfase Ni/electrolito sólido/gas; (ii) el derrame de átomos de potasio sobre la superficie expuesta al gas Ni; y (iii) la difusión de átomos de potasio a las interfaces de límite de grano interno de Ni.

In this article we show for the first time the formation of magnetic supported organic nanowires (ONWs) driven by self-assembly of a nonplanar Fe(III) phthalocyanine chloride (FePcCl) molecule. The ONWs grow by a crystallization mechanism on roughness-tailored substrates. The growth methodology consists of a vapor deposition under low vacuum and mild temperature conditions. The structure, microstructure, and chemical composition of the FePcCl NWs are thoroughly elucidated and compared with those of Fe(II) phthalocyanine NWs by a consistent and complementary combination of advanced electron microscopies and X-ray spectroscopies. In a further step, we vertically align the NWs by conformal deposition of a SiO2 shell. Such orientation is critical to analyze the magnetic properties of the FePcCl and FePc supported NWs. A ferromagnetic behavior below 30 K with an easy axis perpendicular to the phthalocyanine plane was observed in the two cases with the FePcCl nanowires presenting a wider hysteresis. These results open the path to the fabrication of nanostructured one-dimensional small-molecule spintronic devices.

The selective incorporation of deposition species with preferential directionality is analyzed during the growth of TiO thin films by magnetron sputtering. Using wisely-designed collimators, tilted nanocolumnar morphologies are grown in a ballistic deposition regime, i.e. when most deposition species arrive at the film surface along well-defined preferential directions, and also in a thermalized deposition regime, when these species follow an isotropic momentum distribution in the plasma gas. The obtained results suggest that the use of particle collimators may promote the growth of porous thin films even in the classical magnetron sputtering configuration, when the target and the substrate are parallel. General insights are given on this approach and, as a proof of concept, its principles applied for the synthesis of nanostructured films in a laboratory-size reactor.

This work reports about the performance of a Ni/Cu-modified screen printed electrodes (SPE/Ni/Cu), prepared by physical vapor deposition (PVD) in an oblique angle configuration (OAD), for non-enzymatic glucose sensing applications. SPE/Ni/Cu electrodes showed an excellent reversibility and a catalytic behavior for detection of glucose that were controlled by the diffusion of reactants up to the active sites at the electrode surface. The study with a flow injection analysis (FIA) setup of the main experimental variables affecting the detection process has shown that the developed electrode system had an excellent glucose sensitivity of 1.04 AM1cm2 (R2:0.999), a linear response up to 1 mM, a limit of detection of 0.33 mM and a time of analysis of ca. 30 s per sample. The selectivity of the sensor was checked against various interferences, including ascorbic acid, uric acid, acetaminophen and other sugars, in all cases with excellent results. The feasibility of using this sensor for practical applications was successfully confirmed by determining the glucose concentration in different commercial beverages., The financial support for the development of this work has been granted by the FEDER funds of the UE and the projects MAT2013‐40852‐R and MAT2016‐79866‐R from MINECO, 201560E055 from CSIC‐MINECO and RECUPERA2020 from MINECO‐“Fondo social Europeo”. Pedro Salazar thanks RECUPERA 2020 project for financial support.

In this work we analyze a phenomenon that takes place when growing magnetron sputtered porous/compact multilayer systems by alternating the oblique angle and the classical configuration geometries. We show that the compact layers develop numerous fissures rooted in the porous structures of the film below, in a phenomenon that amplifies when increasing the number of stacked layers. We demonstrate that these fissures emerge during growth due to the high roughness of the porous layers and the coarsening of a discontinuous interfacial region. To minimize this phenomenon, we have grown thin interlayers between porous and compact films under the impingement of energetic plasma ions, responsible for smoothing out the interfaces and inhibiting the formation of structural fissures. This method has been tested in practical situations for compact TiO/porous SiO multilayer systems, although it can be extrapolated to other materials and conditions., Authors acknowledge the University of Seville (VPPI-US), the Junta de Andalucía (TEP8067, TEP5283 and P12–2265MO) and the Ministry of Economy and Competitiveness of Spain (MAT2013-42900-P, MAT2013-40852-R, MAT2016-79866-R, MAT2015-69035-REDC) for financial support.

Plasma immersion ion implantation technology has been utilized to enhance the photocatalytic activity of the anatase phase of TiO thin films deposited by cathodic arc evaporation PVD. The main objective of this study is to shift the light absorbance of the titania in order to obtain antibacterial activity under visible light irradiation. TiO thin films, deposited on polished stainless steel AISI 304 and silicon wafers, were implanted with nitrogen ions (N/N ) at 20 kV energy and different temperatures between 250 and 350 °C. The antibacterial activity of nitrogen implanted titania coatings has been monitored for Escherichia coli under visible light irradiation. Additionally ultra violet/visible spectrophotometry tests have been carried out to measure the changes in the light absorbance of the doped films. Further characterization has been performed, including X-ray photoelectron spectroscopy, X-ray diffraction and glow discharge optical emission spectrometry. As a result of Nitrogen implantation, the light absorption peak shifted from ultra violet region (UV-A) to visible wavelength range, which led to an increase of the antibacterial efficacy under visible light irradiation., This work was developed in the framework of the industrial project ACTIONIC (IDI-20140-230-231) supported by the Ministerio de Economía y Competitividad (MINECO), through Centro Desarrollo Tecnológico Industrial (CDTI), and the Government of Navarra through the project DECOBAC.

In this work we report a non-enzymatic sensor for hydrogen peroxide (HO) detection based on nanostructured nickel thin films prepared by physical vapor deposition at oblique angles. Porous thin films deposited on ITO substrates were characterized by X-ray diffraction analysis, scanning electron microcopy (SEMs), X-ray photoelectron spectroscopy (XPS) and electrochemical techniques such as Cyclic Voltammetry (CV) and Constant Potential Amperometry (CPA). The microstructure of the thin films consisted of inclined and separated Ni nanocolumns forming a porous thin layer of about 500 nm thickness. Prior to their use, the films surface was electrochemically modified and the chemical state studied by CV and XPS analysis. These techniques also showed that Ni/Ni species were involved in the electrochemical oxidation and detection of HO in alkaline medium. Main analytical parameters such as sensitivity (807 mA M cm), limit of detection (3.22 μM) and linear range (0.011–2.4 mM) were obtained under optimal operation conditions. Sensors depicted an outstanding selectivity and a high stability and they were successfully used to determine HO concentration in commercial antiseptic solutions., The financial support for the development of this work has been granted by projects MAT2013–40852–R and 201560E055 from MINECO, RECUPERA 2020 from MINECO–“Fondo social Europeo” (FEDER funds). Pedro Salazar thanks the RECUPERA 2020 project for a grant contract.

Oblique angle deposition (OAD) is a powerful technique for the fabrication of porous nanostructured oxide thin films. OAD films typically present a columnar tilted nanostructure due to geometrical shadowing effects during the thin film growth. In this work, we study the fabrication of transparent and conducting indium tin oxide films (ITO) by OAD assisted by a microwave ECR plasma. The objective of assisting the deposition with a plasma discharge is to modify the growth mechanism of the OAD process introducing additional parameters to control the columnar microstructure, composition, porosity of the films. The results indicate the OAD ITO deposition assisted by the plasma discharge is a very effective process to develop in-plane structural anisotropy in the ITO nanocolumnar films what determines their electrical properties.

The main handicap still hindering the eventual exploitation of organometal halide perovskite-based solar cells is their poor stability under prolonged illumination, ambient conditions, and increased temperatures. This article shows for the first time the vacuum processing of the most widely used solid-state hole conductor (SSHC), i.e., the Spiro-OMeTAD [2,2′,7,7′-tetrakis (N,N-di-p-methoxyphenyl-amine) 9,9′-spirobifluorene], and how its dopant-free crystalline formation unprecedently improves perovskite solar cell (PSC) stability under continuous illumination by about two orders of magnitude with respect to the solution-processed reference and after annealing in air up to 200 °C. It is demonstrated that the control over the temperature of the samples during the vacuum deposition enhances the crystallinity of the SSHC, obtaining a preferential orientation along the π–π stacking direction. These results may represent a milestone toward the full vacuum processing of hybrid organic halide PSCs as well as light-emitting diodes, with promising impacts on the development of durable devices. The microstructure, purity, and crystallinity of the vacuum sublimated Spiro-OMeTAD layers are fully elucidated by applying an unparalleled set of complementary characterization techniques, including scanning electron microscopy, X-ray diffraction, grazing-incidence small-angle X-ray scattering and grazing-incidence wide-angle X-ray scattering, X-ray photoelectron spectroscopy, and Rutherford backscattering spectroscopy., The authors thank the “Agencia Estatal de Investigación”, “Consejería de Economía y Conocimiento de la Junta de Andalucía” (US‐1263142), “Ministerio de Economía y Competitividad” (MAT2016‐79866‐R, MAT2013‐42900‐P, FPA2016‐77689‐C2‐1‐R, and MAT2016‐76892‐C3‐2‐R) and the European Union (EU) through cohesion fund and FEDER 2014‐2020 programs for financial support. J.R.S.‐V. and A.B. acknowledge the EU project PlasmaPerovSol and funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska‐Curie grant agreement ID 661480. J.R.S.‐V‐ and M.C.L.‐S. thank the University of Seville through the VI “Plan Propio de Investigación y Transferencia de la US” (VI PPIT‐US). This research has received funding from the EU‐H2020 research and innovation programme under Grant Agreement No. 654360 having benefitted from the access provided by Technische Universität Graz at Elettra—TUG in Trieste (IT) within the framework on the NFFA (Nanoscience Foundries & Fine Analysis) Europe Transnational Access Activity. F.J.A. and J.R.S.‐V. acknowledge the “Juan de la Cierva” and “Ramon y Cajal” national programs, respectively.

We experimentally analyze different growth regimes of Ti thin films associated to the existence of kinetic energy-induced relaxation mechanisms in the material's network when operating at oblique geometries. For this purpose, we have deposited different films by evaporation and magnetron sputtering under similar geometrical arrangements and at low temperatures. With the help of a well-established growth model we have found three different growth regimes: (i) low energy deposition, exemplified by the evaporation technique, carried out by species with typical energies in the thermal range, where the morphology and density of the film can be explained by solely considering surface shadowing processes, (ii) magnetron sputtering under weak plasma conditions, where the film growth is mediated by surface shadowing mechanisms and kinetic-energy-induced relaxation processes, and (iii) magnetron sputtering under intense plasma conditions, where the film growth is highly influenced by the plasma, and whose morphology is defined by nanocolumns with similar tilt than evaporated films, but with much higher density. The existence of these three regimes explains the variety of morphologies of nanocolumnar Ti thin films grown at oblique angles under similar conditions in the literature., The authors thank the European Regional Development Funds program (EU-FEDER) and the MINECO-AEI (201560E055, MAT2014-59772-C2-1-P, and MAT2016-79866-R and network MAT2015-69035-REDC) for financial support. The authors also acknowledge the financial support of the University of Seville (V and VI PPIT-US). The National Center for Accelerators (Seville, Spain) is also acknowledged.

This paper reports a groundbreaking approach for simultaneous hydrogen production and storage that entails catalysis, electrochemistry, surface science, and materials synthesis. A novel electrocatalytic system is developed based on nickel nanocolumnar films of controlled microstructure prepared on K-βAl2O3 solid electrolyte supports by oblique angle physical vapor deposition. The outstanding characteristics of this system are a hydrogen storage capacity of up to 19 g of H2 (100 g of Ni)−1, which is unparalleled in the literature and the possibility of controlling its release electrochemically, under fixed mild conditions (280 °C and normal pressure). H2 is produced in situ by methanol steam re-forming on the Ni catalyst, and it spills over onto graphene oxide aggregates formed during the catalytic process, as confirmed by SEM, FTIR, and Raman spectroscopy. The proposed storage mechanism considers a synergetic contribution of both Ni and graphene oxide, promoted by K+ ions, in enhancing the hydrogen storage capacity of the system., Este documento informa sobre un enfoque innovador para la producción y el almacenamiento simultáneos de hidrógeno que implica catálisis, electroquímica, ciencia de superficies y síntesis de materiales. Se desarrolla un novedoso sistema electrocatalítico basado en películas nanocolumnares de níquel de microestructura controlada preparadas sobre soportes electrolíticos sólidos de K-βAl 2 O 3 mediante deposición física de vapor en ángulo oblicuo. Las características sobresalientes de este sistema son una capacidad de almacenamiento de hidrógeno de hasta 19 g de H 2 (100 g de Ni) -1 , que no tiene paralelo en la literatura y la posibilidad de controlar su liberación electroquímicamente, en condiciones suaves fijas (280 ° C y presión normal). H 2se produce in situ mediante la reformación con vapor de metanol en el catalizador de Ni, y se derrama sobre los agregados de óxido de grafeno formados durante el proceso catalítico, como lo confirman las espectroscopias SEM, FTIR y Raman. El mecanismo de almacenamiento propuesto considera una contribución sinérgica tanto del Ni como del óxido de grafeno, promovida por iones K + , para mejorar la capacidad de almacenamiento de hidrógeno del sistema.

Porous thin films grown at oblique angles by evaporation techniques are formed by tilted nanocolumnar structures which, depending on the material type and growth conditions, associate along certain preferential directions, giving rise to large domains. This arrangement, commonly denoted as bundling association, is investigated in the present work by performing fundamental experiments and growth simulations. It is proved that trapping processes of vapor species at the film surface, together with the shadowing mechanism, mediate the anisotropic widening of the nanocolumns and promote their preferential coalescence along certain directions, giving rise to domains with different shape and size. The role of these two processes is thoroughly studied in connection with the formation of these domains in materials as different as SiO and TiO., The authors thank the Junta de Andalucía (P12-FQM-2265) and the Spanish Ministry of Economy and Competitiveness (Projects, MAT2013-40852-R, MINECO-CSIC 201560E055) for financial support.

The growth of Ti thin films by the magnetron sputtering technique at oblique angles and at room temperature is analysed from both experimental and theoretical points of view. Unlike other materials deposited in similar conditions, the nanostructure development of the Ti layers exhibits an anomalous behaviour when varying both the angle of incidence of the deposition flux and the deposition pressure. At low pressures, a sharp transition from compact to isolated, vertically aligned, nanocolumns is obtained when the angle of incidence surpasses a critical threshold. Remarkably, this transition also occurs when solely increasing the deposition pressure under certain conditions. By the characterization of the Ti layers, the realization of fundamental experiments and the use of a simple growth model, we demonstrate that surface mobilization processes associated to a highly directed momentum distribution and the relatively high kinetic energy of sputtered atoms are responsible for this behaviour, The authors thank Fundación Domingo Martínez, the Junta de Andalucía (P12-FQM-2265) and the Ministry of Science and Innovation (Projects CONSOLIDER CSD2008-00023, MAT2013-42900-P, MAT2013-40852-R, MAT2014-59772- C2-1, MAT2011-29081) for financial support.

This paper presents a study of the mechanical properties and an evaluation of damage mechanisms of nanocolumnar TiO-SiO multilayer coatings prepared by physical vapour oblique angle deposition at different configurations (slanted, zigzag or chiral) and two zenithal evaporation angles (70°or 85°). The characterization at micro- and nanometric length scales of the mechanical properties of the multilayers has been carried out by nanoindentation and nanoscratch tests, while the morphological evaluation of the surface and sub-surface damages produced with a sharp indenter and the adhesive and/or cohesive failures between coating and substrate have been investigated by field emission scanning electron microscopy and focused ion beam, respectively. The obtained results have shown that the main processing parameters controlling the mechanical response of the different multilayers is the zenithal angle of deposition and the number of layers in the multilayer stack, while the coating architecture had only a minor effect on the mechanical response. This analysis also revealed a higher resistance to scratch testing and a brittle failure behaviour for the low zenithal angle coatings as compared with the high angle ones., Furthermore, we would like to thank the support received from Direcció General de Recerca del Comissionat per a Universitats i Recerca de la Generalitat de Catalunya through recognition of CIEFMA as Grup de Recerca Consolidad (2014-SGR-130) and the MINECO (projects MAT2014-60720-R, MAT2013-40852-R and RECUPERA 2020, this latter co-funded with structural funds of the EU). J J R would like to thank the Juan de la Cierva Programme for its financial support (grant number: JCI-2012–14454). MINECO/ICTI2013-2016/MAT2013-40852-R

A new non-destructive method to determine hydrogen content in diamond-like carbon and polymeric thin film materials is developed. The method relies on quantification of the intensity of elastic peak stemming from the backscattering of electrons with the hydrogen atoms present in the samples as measured by reflection electron energy loss spectroscopy. Low current primary electron beams of ∼ 1500 eV are used to minimize hydrogen desorption by electron bombardment and to provide enough energy separation between the elastic signals coming from hydrogen and other atoms (mainly C and O atoms) from the thin film materials. Quantitative analysis of the hydrogen content at the surface of diamond-like carbon thin films is achieved by using phenomenological sensitivity factors of hydrogen against the other atoms with reference to polymeric samples. The validity of the method is checked with elastic recoil detection measurements. A comparison is also made with data provided by infrared spectroscopy analysis of the same samples. We estimate that the error bar in the determination of hydrogen content in the samples is around 20% of the total hydrogen content.