Immobilization of nanomaterials in PMMA composites for photocatalytic removal of dyes, phenols and bacteria from water

Nanomaterials represent a possible solution to solve many of the current issues involving waterquality, but several limitations exist for efficient applications, primarily concerning the dispersionof such nanomaterials in water, their recovery after water treatment and the resulting impact onhuman health and ecosystems. We present an approach based on the incorporation of severalnanomaterials into polymeric composites as a valid solution to overcome these problems. Weembedded active TiO2 nanostructures in poly (methyl methacrylate) (PMMA), with the advantageof no need of recovery of the nanoparticles after water treatment. Furthermore, we combinedtitanium dioxide nanoparticles with single walled carbon nanotubes, as acceptor of electrons, andobtained a significantly higher photocatalytic efficiency under UV irradiation, compared to thesystems with TiO2 only. Photoactive materials even under visible light were synthesized thanks tothe functionalization of the TiO2 nanoparticle surface with meso-tetraphenylporphyrin-4,4’,4’’,4’’’-tetracarboxylic acid (TCPP) as dye sensitizer. We realized these polymeric nanocomposites by lowcostsolution casting and evaluated their photocatalytic activity by degradation of some dyes andphenol in an aqueous medium. A significant antibacterial activity, measured through CFU (ColonyForming Units) count using Escherichia coli as a model organism, is also reported.