Vertically aligned arrays of ZnO nanorod were synthesized on the Au/SiO2/Si(1 0 0) substrate by a simple aqueous solution growth process without pre-prepared ZnO seed layer For comparison glass and SiO2/Si were also used as substrates and the results show that the Au layer plays a decisive role in orienting the growth of the ZnO nanorod The effects of other growth parameters including Zn2+ concentration and growth time on morphology density and orientation of the ZnO nanostructure were also studied and with longer reaction time a new structure namely ZnO nanotip was obtained Moreover the growth mechanism of ZnO nanorod arrays grown on the Au/SiO2/Si substrate was proposed (C) 2010 Elsevier BV All rights reserved