Fabrication of porous ZnO nanostructures and morphology control

Abstract

Abstract Porous ZnO nanostructures were easily fabricated by annealing and etching of as‐grown ZnO nanorods using an aqueous solution method at low temperature. The density of ZnO nanorods was changed by repetition of coating and drying of zinc acetate hydrate in ethanol. The annealing process is a very critical step to make porous ZnO nanorods because nano‐sized pore are formed at this step. Without annealing, pores could not be observed at the surface of ZnO nanorods. Furthermore, pore the size gets larger in etching steps following the annealing. The structural and optical properties for porous ZnO nanostructures were investigated using TEM and PL. Porous ZnO nanostructures were grown along the c‐axis and pores were distributed in the whole body. PL intensity was increased by annealing and etching. This is ascribed to the improved crystallinity and large surface area. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)