Researchers from the Graphene Flagship in Cambridge, U.K., have developed a graphene-titanium dioxide photocatalyst that degrades up to 70% more atmospheric nitrogen oxides than standard titanium dioxide nanoparticles in tests on real pollutants. The composite could represent an effective tool for reducing the amount of NO_x reaching the atmosphere from vehicle exhausts.

The photocatalyst is prepared in a one-step process involving the liquid-phase exfoliation of graphite in the The composite could represent an effective tool for reducing the amount of NOx reaching the atmosphere from vehicle exhausts. Source: G. Guidetti et al.presence of titanium dioxide nanoparticles in water. The resulting graphene-titania nanocomposite can be applied to different surfaces to passively remove atmospheric pollutants from the air. If applied to concrete on streets or building walls, the photodegradation products generated could be washed away naturally by the elements or manually removed.

Tests demonstrated that 40% more rhodamine B, used as a volatile organic pollutant model, was degraded by the graphene-titania composite than by titania alone, in water under UV irradiation.

The strong photocatalytic activity of the material is attributed to rapid electron transfer from the titania to the graphite flakes. Researchers from Universitá di Bologna (Italy), University of Cambridge, Politecnico di Milano (Italy), NEST Istituto Nanoscienze-CNR (Italy), Technion Israel Institute of Technology, Eindhoven University of Technology (The Netherlands) collaborated on this study, which is published in Nanoscale.