Controlled synthesis of ZnO nanostructures with assorted morphologies via simple solution chemistry

In the present investigation, we report the reproducible simple solution chemistry towards synthesis of ZnO nanostructure on fluorine doped tin oxide (FTO) coated glass substrate in aqueous medium at low temperature (>100 °C). The different preparative parameters such as deposition time, bath temperature, concentration of precursor solution, pH of the bath etc. were optimized to get fibrous nanoflakes, nanobeads, nanoparticles, cactus and highly crystalline 1D nanoneedles & hexagonal nanorods of ZnO. However, the as-deposited film consists of mixture of zinc hydroxide [Zn(OH)2] and ZnO. In the present work, to get pure ZnO phase, the as-deposited films were air annealed at relatively lower temperature (200 °C). The annealed ZnO films deposited by CBD and SILAR were characterized for structural, surface morphological, optical properties and surface wettability studies etc. The simplicity of the synthesis route coupled with the variety of ZnO nanostructures is manifest to be an important candidate for nanoscale devices.