Novel low temperature synthesis of ZnO nanostructures and its efficient field emission property

We have developed a novel, simple and cost effective wet chemical synthetic route for the production of ZnO nanoneedles and nanoflowers at low temperature. The synthesis process does not require any surfactant, template or pre-seeding. The synthesized ZnO nanoneedles have very sharp tips with their lengths in the range 2-3 μm, while for the case of nanoflowers, the nanoneedles were bunched together. X-ray diffraction study and X-ray photoelectron spectroscopic studies confirmed the formation of pure ZnO phase. Studies on the electron field emission property of the grown nanostructures showed that they are very efficient field emitter. The turn-on fields and the threshold fields are 3.6 V/μm, 4.4 V/μm and 5.4 V/μm, 6.8 V/μm for the ZnO nanoneedles and ZnO nanoflowers, respectively. The enhanced field emission property was attributed to the presence of sharp tips of the nanostructures.