Open Access
Novel design of superhydrophobic and anticorrosive PTFE and PAA + B - CD composite coating deposited by electrospinning, spin coating and electrospraying techniques
(MDPI, 2022) Vicente Gómara, Adrián; Rivero Fuente, Pedro J.; Urdiroz Urricelqui, Unai; García, Paloma; Mora, Julio; Palomares, F. Javier; Rodríguez Trías, Rafael; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2
A superhydrophobic composite coating consisting of polytetrafluoroethylene (PTFE) and poly(acrylic acid)+ β-cyclodextrin (PAA + β-CD) was prepared on an aluminum alloy AA 6061T6 substrate by a three-step process of electrospinnig, spin coating, and electrospraying. The electrospinning technique is used for the fabrication of a polymeric binder layer synthesized from PAA + β-CD. The superhydrophilic characteristic of the electrospun PAA + β-CD layer makes it suitable for the absorption of an aqueous suspension with PTFE particles in a spin-coating process, obtaining a hydrophobic behavior. Then, the electrospraying of a modified PTFE dispersion forms a layer of distributed PTFE particles, in which a strong bonding of the particles with each other and with the PTFE particles fixed in the PAA + β-CD fiber matrix results in a remarkable improvement of the particles adhesion to the substrate by different heat treatments. The experimental results corroborate the important role of obtaining hierarchical micro/nano multilevel structures for the optimization of superhydrophobic surfaces, leading to water contact angles above 170°, very low contact angle of hysteresis (CAH = 2°) and roll-off angle (αroll−off < 5°). In addition, a superior corrosion resistance is obtained, generating a barrier to retain the electrolyte infiltration. This study may provide useful insights for a wide range of applications.
Open Access
Contribution to the development of functional nanostructured coatings based on silver nanoparticles
(2014) Rivero Fuente, Pedro J.; Goicoechea Fernández, Javier; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Esta tesis se centra en la síntesis de nanopartículas de plata (AgNPs) y su posterior incorporación en recubrimientos delgados usando dos métodos alternativos: el proceso de síntesis in situ (ISS) de AgNPs y la técnica de embebido capa a capa (LbL-E) de AgNPs. Un preciso control de varios parámetros tales como la forma, tamaño, estado de agregación o la distribución de las nanopartículas de plata en los recubrimientos tiene una gran influencia en la posición final de la longitud de onda de la resonancia localizada de plasmones superficiales (LSPR). Además, estas películas que incorporan nanopartículas de plata han sido estudiadas para dos aplicaciones diferentes. La primera aplicación es la fabricación de recubrimientos antibacterianos eficientes. La segunda aplicación es la fabricación de un nuevo tipo de sensores de fibra óptica basados en la incorporación de nanopartículas de plata en películas nanoestructuradas, que hace posible obtener y observar dos resonancias ópticas diferentes, (LSPR) y resonancias de modos con pérdidas (LMR), en un mismo dispositivo
Open Access
Electrospinning technique as a powerful tool for the design of superhydrophobic surfaces
(IntechOpen, 2020) Rivero Fuente, Pedro J.; Vicente Gómara, Adrián; Rodríguez Trías, Rafael; Ingeniería; Ingeniaritza; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA1929
The development of surface engineering techniques to tune-up the composition, structure, and function of materials surfaces is a permanent challenge for the scientific community. In this chapter, the electrospinning process is proposed as a versatile technique for the development of highly hydrophobic or even superhydrophobic surfaces. Electrospinning makes possible the fabrication of nanostructured ultrathin fibers, denoted as electrospun nanofibers (ENFs), from a wide range of polymeric materials that can be deposited on any type of surface with arbitrary geometry. In addition, by tuning the deposition parameters (mostly applied voltage, flow rate, and distance between collector/needle) in combination with the chemical structure of the polymeric precursor (functional groups with hydrophobic behavior) and its resultant viscosity, it is possible to obtain nanofibers with highly porous surface. As a result, functionalized surfaces with water-repellent behavior can be implemented in a wide variety of industrial applications such as in corrosion resistance, high efficient water-oil separation, surgical meshes in biomedical applications, or even in energy systems for long-term efficiency of dye-sensitized solar cells, among others.
Open Access
Layer-by-layer assembly as a powerful nanofabrication technique for the design of antimicrobial surfaces in the textile industry
(Taylor & Francis, 2022) Rivero Fuente, Pedro J.; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2
In this work, the fabrication of multilayer structures has been presented by using the layer-by-layer (LbL) nanoassembly technique with the aim to prevent the bacterial adhesion, pathogen colonization, or even contact-killing bacteria. The use of this nanofabrication technique is of great interest because the resultant thickness of the films can be perfectly controlled as a function of the electrostatic attraction between positive and negative charged compounds. In addition, this technique shows a great versatility because it can be implemented to a wide variety of substrates with any shape and composition (i.e., polymers, composites, medical devices, metallic substrates) without using any expensive equipment. In some cases, the polyelectrolytes can play a dual role for preparing multilayer antimicrobial surfaces. The first one is that most of them can be used for embedding active compounds, which can be released in a further step, while the second one, controlling the pH of the dipping cationic polyelectrolyte solutions can induce the presence of higher protonated charges in the outer surface, which 256can act as a better effective antimicrobial activity. Finally, a perspective in detail of these different approaches will be deeply analyzed against different bacterial strains.
Open Access
Layer-by-layer nano-assembly: a powerful tool for optical fiber sensing applications
(MDPI, 2019) Rivero Fuente, Pedro J.; Goicoechea Fernández, Javier; Arregui San Martín, Francisco Javier; Ingeniaritza; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC; Ingeniería; Ingeniería Eléctrica, Electrónica y de Comunicación
The ability to tune the composition of nanostructured thin films is a hot topic for the design of functional coatings with advanced properties for sensing applications. The control of the structure at the nanoscale level enables an improvement of intrinsic properties (optical, chemical or physical) in comparison with the traditional bulk materials. In this sense, among all the known nanofabrication techniques, the layer-by-layer (LbL) nano-assembly method is a flexible, easily-scalable and versatile approach which makes possible precise control of the coating thickness, composition and structure. The development of sensitive nanocoatings has shown an exceptional growth in optical fiber sensing applications due to their self-assembling ability with oppositely charged components in order to obtain a multilayer structure. This nanoassembly technique is a powerful tool for the incorporation of a wide variety of species (polyelectrolytes, metal/metal oxide nanoparticles, hybrid particles, luminescent materials, dyes or biomolecules) in the resultant multilayer structure for the design of high-performance optical fiber sensors. In this work we present a review of applications related to optical fiber sensors based on advanced LbL coatings in two related research areas of great interest for the scientific community, namely chemical sensing (pH, gases and volatile organic compounds detection) as well as biological/biochemical sensing (proteins, immunoglobulins, antibodies or DNA detection).
Open Access
Machinability of Waspaloy: an investigation of cutting forces and tool wear in turning
(Springer, 2025-07-15) Suárez, Alfredo; Veiga Suárez, Fernando; Sandúa Fernández, Xabier; Rivero Fuente, Pedro J.; López de Lacalle, Luis Norberto; Wretland, Anders; Ingeniería; Ingeniaritza; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA2025-11904
The machinability of Waspaloy, a nickel-based superalloy widely used in aerospace applications due to its excellent mechanical and thermal properties, presents significant challenges during machining processes. This study experimentally investigates the influence of two heat treatment conditions (solution annealing and age hardening) as well as the effect of coolant pressure (conventional and high-pressure cooling) on cutting forces, tool wear, and chip morphology during the turning of Waspaloy. Quantitative and qualitative analyses were performed on tool wear types including rake face, flank, and notch wear, while chip morphology was also evaluated to gain deeper insight into the machinability behavior. The results show that high pressure cooling (HPC) improves machinability by reducing cutting forces and minimizing wear, particularly in solution-annealed, large grain samples. In contrast, age-hardened specimens with conventional cooling exhibited the highest wear and cutting forces due to increased hardness and insufficient thermal dissipation. Overall, the findings highlight that both coolant pressure and heat treatment significantly influence the wear mechanisms and cutting performance, with HPC and lower hardness conditions enhancing the machinability of Waspaloy. This work uniquely combines the effects of dual heat treatments and cooling pressures to comprehensively evaluate their combined impact on Waspaloy machinability, providing new insights into optimizing cutting performance and tool life for this challenging superalloy.
Open Access
Designing multifunctional protective PVC electrospun fibers with tunable properties
(MDPI, 2020) Rivero Fuente, Pedro J.; Rosagaray Burdaspar, Iker; Fuertes Bonel, Juan Pablo; Rodríguez Trías, Rafael; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Ingeniería; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA1929
In this work, the electrospinning technique is used for the fabrication of electrospun functional fibers with desired properties in order to show a superhydrophobic behavior. With the aim to obtain a coating with the best properties, a design of experiments (DoE) has been performed by controlling several inputs operating parameters, such as applied voltage, flow rate, and precursor polymeric concentration. In this work, the reference substrate to be coated is the aluminum alloy (60661T6), whereas the polymeric precursor is the polyvinyl chloride (PVC) which presents an intrinsic hydrophobic nature. Finally, in order to evaluate the coating morphology for the better performance, the following parameters-such as fiber diameter, surface roughness (Ra, Rq), optical properties, corrosion behavior, and wettability-have been deeply analyzed. To sum up, this is the first time that DoE has been used for the optimization of superhydrophobic or anticorrosive surfaces by using PVC precursor for the prediction of an adequate surface morphology as a function of the input operational parameters derived from electrospinning process with the aim to validate better performance.
Open Access
Modelización y estudio experimental y mediante CFD de un ventilador para alumnos de Grado en Ingeniería Mecánica y de Tecnologías Industriales
(Dykinson, 2021) Fuertes Bonel, Juan Pablo; Torres Salcedo, Alexia; Rivero Fuente, Pedro J.; Armañanzas Goñi, Javier; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2
El trabajo planteado en esta comunicación tiene como principales objetivos por un lado, el conocimiento del funcionamiento un ventilador y por el otro, el empleo de softwares propios del diseño (CAD) y de la Mecánica de Fluidos (CFD). Con esto, se busca que el alumno amplíe y afiance sus conocimientos de una máquina fluidomecánica vista en el aula y también, que aprecie la importancia que tiene en ingeniería el trabajo multidisciplinar. Se ha escogido un ventilador, ya que por un lado, su modelización en CAD es más sencilla frente a otras máquinas hidráulicas, como puede ser una bomba centrífuga, y por el otro, porque dentro de las asignaturas de los distintos grados, el estudio del ventilador se realiza en menor profundidad, que el de las máquinas hidráulicas. El trabajo del alumno consta de tres partes diferenciadas: experimentación, diseño y simulación mediante CFD. En la experimentación, el objetivo es que el alumnado pueda manipular un ventilador en el laboratorio contrastando lo visto en teoría con la realidad, y que mediante una toma de datos establecida previamente, se familiarice con su funcionamiento. El siguiente paso consiste en diseñar en CAD la máquina y de esta manera, que puedan poner en práctica lo aprendido en asignaturas anteriores, en cuanto a diseño en CAD se refiere. Por último, y como complemento a las clases sobre CFD, que se imparten en la asignatura donde está programado este trabajo, se pide que el alumnado sea capaz de simular el funcionamiento del ventilador experimentado.
Open Access
Hydrophobic and corrosion behavior of sol-gel hybrid coatings based on the combination of TiO2 NPs and fluorinated chains for aluminum alloys protection
(MDPI, 2018) Rivero Fuente, Pedro J.; Maeztu Redin, Juan Deyo; Berlanga Labari, Carlos; Miguel, Adrián; Rodríguez Trías, Rafael; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Ingeniería; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, Navarre-PRO-UPNA18-6107-FRRRIO
In this work, layers of a sol-gel hybrid matrix doped with metal oxide nanoparticles (TiO2 NPs) have been deposited on flat samples of AA6061-T6 aluminum alloy using the dip-coating technique, with the aim of obtaining coatings with better anti-corrosive and hydrophobic properties. Two different organic modified silica alkoxides, namely 3-(glycidyloxypropyl)trimethoxysilane (GPTMS) and methyltriethoxysilane (MTEOS), have been used for an adequate entrapment of the metal oxide nanoparticles. In addition, a fluorinated metal-alkoxide precursor has also been added to the hybrid matrix in order to improve the hydrophobic behavior. The experimental results corroborate that the presence of these TiO2 NPs play an important role in the development of the sol-gel hybrid coatings. The water contact angle (WCA) measurements, as well as pencil hardness tests indicate that TiO2 NPs make a considerable increase in the resultant hydrophobicity possible, with better mechanical properties of the coatings. The coating thickness has been measured by cross-section scanning electron microscopy (SEM). In addition, a glow discharge optical emission spectroscopy (GD-OES) analysis has been carried out in order to corroborate the adequate entrapment of the TiO2 NPs into the sol-gel coatings. Finally, potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS) have been performed in order to evaluate the corrosion resistance of the coatings. All the results provide insights into the efficacy of the developed sol-gel hybrid coatings for anticorrosive purposes with good mechanical properties.
Open Access
An antibacterial surface coating composed of PAH/SiO2 nanostructurated films by layer by layer
(Wiley, 2010) Urrutia Azcona, Aitor; Rivero Fuente, Pedro J.; Ruete Ibarrola, Leyre; Goicoechea Fernández, Javier; Fernández Valdivielso, Carlos; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería; Ingeniaritza; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC
In this work we propose a novel antibacterial coating composed of SiO2 and the polymer Poly(allylamine hydrochloride) (PAH). The coating was fabricated by the technique Layer-by-Layer (LbL). This technique has already been used in previous works, and it has the advantage that it allows to control the construction of nanosized and well organized multilayer films. Here, the new nanotexturized LbL SiO2 surface acts as antibacterial agent. The fabricated coatings have been tested in bacterial cultures of genus Lactobacillus to observe their antibacterial properties. It has been demonstrated these PAH/SiO2 coating films have a very good antimicrobial behaviour against this type of bacteria.