Diameter dependent photocatalytic activity of ZnO nanowires grown by vapor transport technique

► We have synthesized ZnO NWs of different diameters via vapor transport method. ► Photocatalytic activity of ZnO NWs of various diameters (30-300 nm) were studied. ► Photocatalytic activity was found to increase anomalously for NWs with d < 90 nm. ► The increased activity of thinner NWs is due to higher surface to volume ratio.