Zn-doped titania nanoparticles as building blocks for solid foam filters of water and air via photocatalytic oxidation

Photocatalytic oxidation (PCO) could provide energy-efficient purification of water and air. Its efficacy is constrained mainly by limited photocatalytic activity and active surface. To address both, solid foams with hierarchic porous structures spanning multiple length-scales, stabilized by photocatalytic Zn-doped titania nanoparticles (NP) were synthesized and tested. The NP were characterized by SEM, EDS, DLS, XRD, Raman and UV–Vis spectroscopies. Solid foams were stabilized by NP complexes with cationic surfactants. The foam morphology was characterized and photocatalytic activity was demonstrated in water. The present work paves the way for the development of efficient systems for air and water purification in demanding technological sectors, such as aerospace..