Nanoparticles (NPs) hold great potential for diverse applications, including catalysis, gas adsorption, and air or liquid filtration. However, unlocking their full capabilities often requires assembling them into larger, functional architectures. Among such structures, porous solid foams offer unique advantages due to their high surface area, low density, and interconnected structures. This doctoral research addresses the development and characterization of porous solid foams composed of titanium dioxide (TiO₂) nanoparticles and UV-transparent borosilicate glass with potential photocatalytic applications. The foams were fabricated via the gelcasting method, by direct foaming of bicomponent NP dispersions, composed of amphiphilic surfactant coated TiO₂ complexes and hydrophilic glass particles, using poly(vinyl alcohol) (PVA) as a polymeric matrix and a double-syringe foaming approach. Selective interfacial adsorption drives the spatial segregation of TiO₂ at the pore surface and BS glass particles contribute to the consolidation of the overall structure, thus combining photocatalytic efficiency with mechanical stability. The foams were thermally treated to remove the polymer matrix and consolidate the structure at moderate temperatures (~650 °C) which preserve the anatase phase of TiO₂ and promotes sintering of the glass particles into a mechanically robust network. Morphological parameters such as pore size, connectivity, open porosity, and structural integrity were optimised and both quantitatively and qualitatively assessed. The work contributes to the field of structured photocatalytic materials by providing a reproducible route to fabricate durable and active porous systems, with potential applications in environmental remediation and light-driven chemical processes.
Le nanoparticelle (NPs) hanno un grande potenziale per diverse applicazioni, tra cui la catalisi, l'adsorbimento di gas e la filtrazione di aria e liquidi. Comunque, per sfruttare appieno le loro capacità è spesso necessario assemblarle in architetture funzionali di maggiori dimensioni. Tra queste strutture, le schiume solide porose offrono vantaggi unici grazie alla loro elevata area superficiale, alla bassa densità e alle strutture interconnesse. Questa ricerca di dottorato affronta lo sviluppo e la caratterizzazione di schiume solide porose composte da nanoparticelle di biossido di titanio (TiO₂) e vetro borosilicato trasparente ai raggi UV con potenziali applicazioni fotocatalitiche. Le schiume sono state fabbricate tramite il metodo del gelcasting, schiumando direttamente dispersioni di NP bicomponenti, composte da complessi anfifilici di TiO₂ rivestiti di tensioattivi e particelle di vetro idrofile, utilizzando il poli(alcool vinilico) (PVA) come matrice polimerica e con un approccio di schiumatura a doppia siringa. L'adsorbimento interfacciale selettivo guida la segregazione spaziale di TiO₂ sulla superficie dei pori e le particelle di vetro borosilicato contribuiscono al consolidamento della struttura complessiva, combinando così efficienza fotocatalitica e stabilità meccanica. Le schiume sono state trattate termicamente per rimuovere la matrice polimerica e consolidare la struttura a temperature moderate (~650 °C) che preservano la fase anatasio di TiO₂ e promuovono la sinterizzazione delle particelle di vetro in una rete meccanicamente robusta. I parametri morfologici come la dimensione dei pori, la connettività, la porosità aperta e l'integrità strutturale sono stati ottimizzati e valutati quantitativamente. Il lavoro contribuisce al campo dei materiali fotocatalitici strutturati fornendo un percorso riproducibile per fabbricare sistemi porosi durevoli e attivi, con potenziali applicazioni nella riparazione ambientale e nei processi chimici guidati dalla luce.
Development of porous materials with tailored structural and functional properties
NAVARRO ARREBOLA, IVÁN
2025
Abstract
Nanoparticles (NPs) hold great potential for diverse applications, including catalysis, gas adsorption, and air or liquid filtration. However, unlocking their full capabilities often requires assembling them into larger, functional architectures. Among such structures, porous solid foams offer unique advantages due to their high surface area, low density, and interconnected structures. This doctoral research addresses the development and characterization of porous solid foams composed of titanium dioxide (TiO₂) nanoparticles and UV-transparent borosilicate glass with potential photocatalytic applications. The foams were fabricated via the gelcasting method, by direct foaming of bicomponent NP dispersions, composed of amphiphilic surfactant coated TiO₂ complexes and hydrophilic glass particles, using poly(vinyl alcohol) (PVA) as a polymeric matrix and a double-syringe foaming approach. Selective interfacial adsorption drives the spatial segregation of TiO₂ at the pore surface and BS glass particles contribute to the consolidation of the overall structure, thus combining photocatalytic efficiency with mechanical stability. The foams were thermally treated to remove the polymer matrix and consolidate the structure at moderate temperatures (~650 °C) which preserve the anatase phase of TiO₂ and promotes sintering of the glass particles into a mechanically robust network. Morphological parameters such as pore size, connectivity, open porosity, and structural integrity were optimised and both quantitatively and qualitatively assessed. The work contributes to the field of structured photocatalytic materials by providing a reproducible route to fabricate durable and active porous systems, with potential applications in environmental remediation and light-driven chemical processes.File | Dimensione | Formato | |
---|---|---|---|
phdunige_5355011.pdf
accesso aperto
Dimensione
8.75 MB
Formato
Adobe PDF
|
8.75 MB | Adobe PDF | Visualizza/Apri |
I documenti in UNITESI sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/20.500.14242/295851
URN:NBN:IT:UNIGE-295851