Multifunctional graphene oxide-TiO₂-Ag nanocomposites for high performance water disinfection and decontamination under solar irradiation.

Multifunctional nanocomposites (GO-TiO2-Ag) integrating 2D GO sheets, 1D TiO2 nanorods and 0D Ag nanoparticles were synthesized via a facile two-phase method and characterized by various analytical techniques including TEM, EDS and XRD. The GO-TiO2-Ag nanocomposites demonstrate remarkably enhanced photocatalytic activities in degrading AO 7 and phenol under solar irradiation compared with GO-TiO2 and GO-Ag. They also exhibit excellent intrinsic antibacterial activity toward Escherichia coli, as well as significantly enhanced photo-biocidal capability over GO-TiO2 and GO-Ag. Through systematically investigating the influence of Ag content in the nanocomposites for their photocatalytic activities, it indicates that the optimal Ag content in the GO-TiO2-Ag nanocomposites varies for dye degradation and for phenol/bacterial degradation with different mechanisms. The superior photocatalytic activities under solar irradiation and the easy recovery make the GO-TiO2-Ag nanocomposites a good promising candidate for water purification.