ZrO2 nanofibers with different surface roughness were employed as supports for the deposition of Pt nanostructures. When the nanofibers had a smooth surface, both homogeneous and heterogeneous nucleation took place, producing Pt nanoparticles deposited on the nanofibers and free-standing Pt nanostars in the solution. By reducing the concentration of Pt precursor, Pt nanowires were formed on the nanofibers. For nanofibers with a rough surface, Pt nanoparticles were formed on the nanofibers through heterogeneous nucleation. These results demonstrate that the surface roughness had a significant impact on the nucleation mechanism and the morphology of the resultant Pt nanostructures. (C) 2009 Elsevier B.V. All rights reserved.