Density-controlled growth of aligned ZnO nanowire arrays by seedless chemical approach on smooth surfaces

A novel ZnO seedless chemical approach for density-controlled growth of ZnO nanowire (NW) arrays has been developed. The density of ZnO NWs is controlled by changing the precursor concentration. Effects of both growth temperature and growth time are also investigated. By this novel synthesis technique, ZnO NW arrays can grow on any substrate (polymer, glass, semiconductor, metal, and more) as long as the surface is smooth. This technique represents a new, low-cost, time-efficient, and scalable method for fabricating ZnO NW arrays for applications in field emission, vertical field effect transistor arrays, nanogenerators, and nanopiezotronics.