Effect of nanosphere monolayer on the morphology of ZnO nanowires grown by hydrothermal method

Abstract

Very high aspect ratio ZnO nanowires have been prepared by a novel nanosphere assisted hydrothermal method. The wires were synthesized on a ZnO seed layer, which was covered by a monolayer of Stöber silica nanoparticles. The so formed nanowires were ca. 30nm in width and up to 7μm in length in contrast with the thicker (60nm) and shorter (0.85μm) ones grown without nanoparticle film under identical conditions. Larger nanoparticles result in shorter nanowires, but the diameter of the nanowires is not affected by the particle diameter in the investigated size range (240–450nm). The thin nanowires show superior photoresponse upon exposure to 360nm UV light compared to those grown without cap layer.