Optimización de la reología de componentes fotocatalíticos para aplicaciones avanzadas en elementos de fachada

Résumé

This thesis discusses the development of a new methodology for 3D printing of TiO2 nanoparticles and its applications in air purification and hydrogen production. A dosage has been obtained that allows 3D printing by DIW (Direct Ink Writing), based on chemical sintering. For this, it requires a paste of high acidity, together with a thermal post-treatment with a minimum temperature of 150°C, without the need for the use of binders. In this way prints are obtained, whose structure is formed exclusively by TiO2 nanoparticles joined by oxygen bridges. The prints obtained by means of this methodology, presents a high photocatalytic activity, showing a great photooxidation capacity of acetaldehyde. In addition, through different combinations of acid and post-treatment temperature, modifications in the reaction mechanisms can be obtained, allowing a greater adaptability to other compounds that are to be degraded. The lower process limitations and reduction of the temperature of the post-treatment compared to previous methodologies, have allowed the incorporation of the titania 3D printing to the surface of different construction materials, such as glass, aluminium or cementitious materials. In this way, a new photocatalytic façade concept is obtained, which presents an increase in photocatalytic activity compared to other previously developed solutions. Finally, the incorporation of preformed gold nanoparticles on the titania prints has been studied, with satisfactory results in the production of hydrogen through the photoreforming of ethanol.