Alvaro Gil

University of Santiago de Compostela | USC · Instituto de Cerámica

In this study, aqueous colloidal ZnO inks with tailored rheological properties have been developed for 3D printing of periodic structures. These periodic structures consisting of alternating layers with tetragonal symmetries were fabricated by extrusion of ZnO inks with concentration of 48 vol%. The as-prepared structures had well-defined and inter...

Reported here is the fabrication and characterization of a three-dimensional photonic crystal for terahertz frequencies based on 3D printing of Al2O3. Specific inks containing Al2O3, the material required for the structure, are synthesized with the viscosity and rheological properties necessary to be extruded through nozzles of micrometric section....

A straightforward manufacture strategy is proposed to obtain an efficient and robust palladium-alumina (Pd 0 /Al 2 O 3) cermet monolithic catalyst, specifically designed to perform safe microwave assisted organic synthesis (MAOS). In this approach, a cermet catalyst with high surface area, controlled composition and adapted shape and dimensions to...

This chapter deals with the study of the possibility of using yellow clay - which was only used in pottery so far- in the civil engineering field as building materials, especially in the field of fired bricks. With the aim to improve the technological properties of yellow clay based bricks, two wastes were used as secondary raw materials. The first...

This paper describes the first example of a 3D printed metal-free graphene oxide-Al2O3 (GO-Al2O3) catalytic system and evaluates its catalytic performance in model transformations. A new functional architecture creates synergies to combine the excellent catalytic effect and reaction scope of graphene oxide, the chemical stability and recyclability...

This work investigates the recycling of pyrrhotite ash (PA) waste as a method to provide a secondary raw material for clay brick bodies. PA is an industrial waste mainly composed by iron oxide particles (64,9 wt%). It was produced during the production of sulfuric acid from the combustion of pyrrhotite ore. This waste was characterized by X-ray flu...

ZnO has been demonstrated to be a promising material for optoelectronic applications in the terahertz (THz) spectral range. However, there have been no reports regarding the fabrication of ZnO structures to control THz radiation, as photonic crystal (PCs) materials. Here, we focus on the development of a functional ZnO PCs for the THz band. The fun...

Composites of reduced graphene oxide (rGO) and Al2O3 with complex three-dimensional (3D) mesoscale architecture were prepared by a combination of 3D printing technique and thermal reduction process. For this purpose, stable aqueous graphene oxide (GO) suspensions were prepared using GO sheets synthesized previously from graphite powders according t...

The development of three-dimensional (3D) patterned Cu-based composites with Al2O3 matrix has significant potential for an array of uses in industrial applications ranging from aerospace to catalysis. However, to date, it was not possible to fabricate complex structures of these composites by applying conventional techniques. The 3D printing techni...

Two 3D-hybrid monolithic catalysts containing immobilized copper and palladium species on a silica support were synthesized by 3D printing and a subsequent surface functionalization protocol. The resulting 3D monoliths provided a structure with pore sizes around 300 μm, high mechanical strength, and easy catalyst recyclability. The devices were des...

This article reports the synthesis and characterization of three-dimensionally ordered macroporous (3DOM) of CaCu3Ti4O12 (CCTO) ceramics. 3DOM structures were prepared by combining sol-gel synthesis with colloidal crystal templating. This was followed by a thermal treatment at different calcination temperatures under air atmosphere. The effect of t...

A catalytic methodology is reported that enables the efficient, operationally simple and environmentally friendly synthesis of diverse 1,4-dihydropyridines and 3,4-dihydropyrimidin-2(1H)-ones, including some relevant drugs and pharmacologically active derivatives. This strategy is based on the use of a 3D printed Al2O3 woodpile material that was si...

This work concerned the physicochemical characterization of an industrial waste which is the pyrrhotite ash from south west of Morocco. A physical and hydrodynamic analyzes were carried out, namely loss on ignition, moisture content, pH, solubility, density and granulometry, as well as chemical, morphological and mineralogical analyzes by SEM, XRF,...

We describe a terahertz time-domain spectrometer developed to perform measurements by reflection under a wide range of angles. The different parts of the device are described as well as the process of frequency-scale calibration and signal linearity evaluation. Also the main parameters that characterize the system and account their performance are...

We herein document the first example of a reliable copper-catalysed Huisgen 1,3-dipolar cycloaddition under oxidative conditions. The combined use of two polymer-supported reagents (polystyrene-1,5,7-triazabicyclo[4,4,0]dec-5-ene/Cu and polystyrene -2-iodoxybenzamide), overcomes the thermodynamic instability of copper (I) species toward oxidation,...

Inks of titanium diisopropoxide bisacetylacetonate ([(CH3)2CHO]2Ti(C5H7O2)2) are suitable for the fabrication of photonic bandgap materials by direct ink writing (DIW). Using this method we are able to obtain micro-periodic titania (TiO2) structures with high refractive index by calcining the structures built with those inks. Calcining at high temp...

We show how confocal microscopy can be used as a simple, fast and flexible technique to fabricate multiple diffractive masks on a single plate. These masks are useful to make full bandgap photonic crystals with a woodpile structure in a single illumination step. The versatility for the control of the confocal microscope allows to define the illumin...

Sistema catalítico híbrido que encapsula al menos un ión metálico por interacción directa con la matriz. Sistema catalítico híbrido, químicamente estable, que comprende nanopartículas de una matriz polimérica inorgánica no funcionalizada constituida por sílice, titania o circonia y que encapsulan al menos un ión metálico por interacción directa con...

La presente invención describe un sistema catalítico híbrido químicamente estable que comprende nanopartículas de sílice, titania o circonia no funcionalizadas y un complejo organometálico de un metal de transición. En los nuevos materiales descritos las especies catalíticas son encapsuladas en la matriz polimérica por interacción directa con la mi...

Sol-gel Inks based in titanium diisopropoxide bisacetylacetonate were prepared to develop nanostructures using the direct ink writing technique. This technique facilitates the structuring of materials by micro extrusion for the fabrication of three-dimensional photonic crystals with high refractive index at micro and nano scale. Thermal treatment o...

Sol-gel Inks based in titanium diisopropoxide bisacetylacetonate were prepared to develop nanostructures using the direct ink writing technique. This technique facilitates the structuring of materials by micro extrusion for the fabrication of three-dimensional photonic crystals with high refractive index at micro and nano scale. Thermal treatment o...

Colloidal crystals of silica spheres functionalized with N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride have been formed by the Langmuir–Blodgett methodology (LB). Monolayers at the air/water interface of functionalized silica spheres have been characterized by surface pressure–area and surface potential–area isotherms and by Brewster ang...

We report a method that combines Brewster angle microscopy and Langmuir-Blodgett films technique to obtain highly ordered 2D colloidal crystals of nanospheres. The deposition of Langmuir-Blodgett films of silica spheres monitored by Brewster angle microscopy allows to determine with accuracy the best physical conditions to transfer highly ordered m...

J-Aggregates of the amphiphilic symmetrical cyanine dye 5,5′-6,6′-tetrachloro-1,1′-diethyl-3,3′-dioctadecyl-benzimidazolocarbocyanine toluenesulfonate are formed in monolayers of the pure dye at the air-water interface as well as in mixtures with the coaggregates hexadecane (HD) and methyl octadecanoate (MOD), respectively, at a molar ratio of dye/...

This paper reports the surface pressure-area isotherms for the new fluorescent probe w-[6-(N-methyl-N-ethylamino)naphthoyl]undecanoic acid (MANA10-2) obtained by changing experimental variables such as the subphase conditions, pH, temperature, and the compression rate. The surface monolayer technique was used in combination with surface fluorescenc...

Formation of J-aggregates of the amphiphilic merocyanine 3- octadecyl-2-[3,3-dicyano-allyliden]benzoxazolin (S118) in monolayers at the air-water interface has been investigated in the absence and presence of the additives (coaggregates, CA) octadecane, methylstearate, octadecanoic acid, and octadecanol, respectively, in the molar ratio S118/CA = 1...

In this work, the surface and fluorescent behavior of three phospholipids containing a pyrene molecule in one of their hydrocarbon chains was studied. Differences between the isotherms provided by the different monolayers can be attributed to the orientation of the head group in the phospholipids at the air/water interface. This assertion is suppor...

Cyclosporin-A (CsA) is a pharmaceutical product which has a polypeptide structure and immunosuppressive activity. It may be administered in the form of liposomes, and this has a series of advantages. Therefore, in this paper, the possible interaction between CsA and phospholipids is studied. The superficial monolayer technique has been used as a li...

The surface monolayer technique was used to study the properties of biomembrane-like systems. The technique was used in combination with surface fluorescence measurements of fluorescent probes incorporated into a phospholipid matrix. Two types of fluorescent probe containing the chromophore pyrene bound to the hydrocarbon tail and the amino group o...

Systems consisting of cyclosporin A (CsA), a cyclic peptide which is an effective immunosuppressive agent for transplanted organs, and dipalmitoylphosphatidylcholine (DPPC), a liposomal phospholipid, obey the molecular area additivity rule when spread as mixed monolayers at the air/water interface. This behaviour is ascribed to the immiscibility of...

The steady-state fluorescence quenching technique was used to investigate the effect of the presence of a series of alcohol homologues of mid-sized straight chain on the size of mixed micelles of sodium dodecyl sulfate (SDS). We used pyrene at concentration of ca 10(-6) M, where only its monomer exhibits any fluorescence, as fluorescent probe, and...