Enhanced Photocatalytic Efficiency of TiO2 Membrane Decorated with Ag and Au Nanoparticles

Ag and Au nanoparticles (NPs) were decorated on the surface of TiO2 membranes by two methods, i.e., hydrothermal synthesis and photoreduction. The size of Ag and Au NPs on the surface of TiO2 membranes was dependent on the method of preparation and varied from 2 nm-10 nm. The photocatalytic performance of the TiO2 particle, TiO2 membrane and the Ag/Au-decorated TiO2 membrane was tested for the catalytic degradation of Rhodamine B (RhB) and Escherichia coli (E. coli) under irradiation of visible light. The experiment results showed that both Ag- and Au-decorated TiO2 membranes exhibited excellent photocatalytic activity in the visible light region. Among the prepared materials, Ag-decorated TiO2 membranes prepared by photoreduction showed the highest activity, which could be attributed to the local surface plasmon resonance (LSPR) effect of the noble metal.