Dissolution–recrystallization and regrowth mechanism of hydrothermally derived six faceted prismatic hexagonal ZnO microrods

Zinc oxide (ZnO) microstructures have been grown using simple hydrothermal method. X-ray data confirms well crystalline nature of obtained ZnO powder with hexagonal (wurtzite-type) crystal structure. Scanning electron microscopic observations reveals that the microstructure consists of well defined sharp prismatic hexagonal microrods with angular walls. The microrods grown with controllable diameter in the range of 1.2–1.5 μm with length in the range of 8–10 μm and grow along the [0 0 0 1] direction. The aspect ratio of ZnO microrods increases with increase in reaction time. It is due to the dissolution–recrystallization mechanism and regrowth process. Morphological observations confirm that the reaction time plays a vital role to determine dimensionality of the synthesized ZnO microrods. The photoluminescence (PL) spectrum of the as-grown ZnO nanostructure reveals a near-band-edge (NBE) emission peak (399 nm) and a blue emission peak (460 nm). The increase in reaction time reveals enhancement in photoluminescence intensity.