Electrospun titania fibers by incorporating graphene/Ag hybrids for the improved visible-light photocatalysis

Abstract

A novel graphene/Ag nanoparticles (NPs) hybrid (prepared by a physical method (PM)) was incorporated into electrospun TiO2 fibers to improve visible-lightdriven photocatalytic properties. The experimental study revealed that the graphene/Ag NPs (PM) hybrid not only decreased the bandgap energy of TiO2, but also enhanced its light response in the visible region due to the surface plasmon resonance (SPR) effect. In addition, compared with those of TiO2 fibers incorporating the graphene/Ag NPs hybrid (prepared by a chemical method (CM)), TiO2-graphene/Ag NPs (PM) fibers exhibited a higher surface photocurrent density and superior photocatalytic performance, i.e., the visible-light-driven photocatalytic activity was enhanced by 2 times. The main reasons include a lower surface defect density of the graphene/Ag NPs (PM) hybrid, a smaller particle size (10 nm) and a higher dispersity of Ag NPs, which promote the rapid transfer of photoexcited charge carriers and inhibit the recombination of photogenerated electrons and holes. It is expected that this kind of ternary electrospun fibers will be a promising candidate for applications in water splitting, solar cells, CO2 conversion and optoelectronic devices, etc.