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Trabajo presentado en la 6th European Conference on Environmental Applications of Advanced Oxidation Processes (EAAOP6), celebrada en Portorož (Eslovenia), del 26 al 30 de junio de 2019, Self-cleaning and anti-fogging technology is already used in a variety of the products today, among which glazing products prevail. Their function is based on two principles, either hydrophobicity (Lotus effect) or photocatalytic hydrophilicity. In the latter case, the self-cleaning action is based on the combination of photocatalysis and photoinduced superhydrophilicity, where dirt removal by uniform spreading of water over the whole surface is improved with photocatalytic decomposition of organic contaminants (Zhang et al., 2012). In spite of the high readiness level of this technology, with competitive products already in the market, there is room to improve the properties of existing self-cleaning and anti-fogging surfaces by designing and tailoring new nanoarchitectures for light-activated thin films (Lavrenčič Štangar et al., 2014). Among photoactive materials, TiO2 gathers nearly all the desired characteristics of a photocatalyst, with the main exception that it is only active under UV light and thus can only use around 5% of the solar spectrum. The synthesis and applications of titania 1D and 2D structures such as nanorods, nanowires and nanotubes has increased in the last decades due to their singular properties in terms of surface area, charge separation and transport, and tuneability (Fresno et al., 2014). In this work, we have obtained highly regular TiO2 nanostructures by oxidation of metallic Ti nanocolumns (NCs) obtained on silicon wafers by the so-called glancing angle deposition technique by magnetron sputtering (MS-GLAD). MS-GLAD is a powerful technique for producing nanostructured coatings in large areas and with a large variety of morphologies (Izquierdo-Barba et al., 2015). In addition, the TiO2 NCs have been decorated with gold nanoparticles (NPs) by means of high-power impulse magnetron sputtering (Mayoral et al., 2019).

La Asociación Universitaria Fabricar e Investigar (AUFI) surge por iniciativa de dos profesores de la Escuela Técnica Superior de Arquitectura de Sevilla: Julián Sobrino Simal y Enrique Larive López. Formada fundamentalmente por alumnos de arquitectura y arquitectos titulados, esta asociación nace con la pretensión de crear un grupo que adquiera destrezas en técnicas de investigación sobre Patrimonio Industrial.

Póster presentado en el Congreso Fuerzas y Tunel, celebrado en San Lorenzo de El Escorial del 12 al 14 de septiembre de 2012., Kelvin probe force microscopy ( KPFM) is a powerful atomic force microscope (AFM)-based technique to meas ure the local variations of surface potential at the nanoscale. It operates by detecting the difference of the work function between a fixed substrate and a conducting movable probe. By modulating the applied potent ial on the probe until the electric force between sample and tip is extinguish ed, it is possible to deter mine the local potential of the surface. KPFM has been extensively us ed to characterize the electrical properties of a wide variety of samples, from semiconductors to biomolecules. As KPFM spatial resolution is intrin sically limited by the long range of the electrostatic interaction, many contri butions on this technique are aimed to improve this feature. Some of them include operating in high vacuum and the development of specialized probes to operate in ambient conditions as, for example, the use of carbon nanotubes or coaxial AFM probes that are electrically shielded everywhere exc ept the very end of the tip. Here we present the use of standar d silicon tips modified by the deposition of gold nanoparticl es. These tips have recent ly shown to improve the aspect ratios and spatial resolution of AFM images. The silicon tips are modified by deposition of nan oclusters of nominal diam eter of 2-3 nm under ultrahigh vacuum conditions using an ion cluster source. In an attempt to extend this enhancement of the resolution and sensitivity to the electrical measurements under ambient conditions, we have performed a KPFM analysis of several samples that include Au and Ag nanoparticles , graphene flakes on silicon dioxide, single-wall carbon nanotubes and double-stranded DNA molecules. The results are compared with similar measurements performed with conventional metallic tips (PtIr5 coated tips). We show that both, topography and surface potent ial images present evid ent improvements when recorded with Au-nanoparticle modified tips

Trabajo presentado a NanoSpain 2010 celebrado en Málaga del 23-26 Marzo, 2010. -- Incluye comunicación oral y póster., Experimental evidence of a monotonous decrease of the capillary forces between hydrophilic surfaces with increasing relative humidity from 0 to 100% is presented. In concordance with the results of a theoretical simulation, we identified the objects’ shape as the origin of different adhesion force vs. RH behaviours when treating with nanoscale objects. If the water neck is formed between a flat surface and a nanometric object presenting a truncated cone shape the adhesion force decreases with increasing vapour pressure. The variety of meniscus force behaviours found for different shapes emphasizes the importance of geometry in capillary phenomena at the nanometric scale.