Development of uniformly grown ZnO micro-particles structures by simple and cost-effective chemical drop methodAuthor(s): M.Prashantha, M.Sekhar Babu, N.Koteeswara Reddy, K.Ramesh
A simple and cost-effective chemical drop method has been developed and adopted for the synthesis of zinc oxide (ZnO) structures. The depositions were carried out at different substrate temperatures increased from100 to 250 oC on glass substrates by dropping an equimolar solution consisting of zinc nitrate hexahydrate and hexamethylenetetramine dissolved in deionized-water with a concentration of 5 mM. The structures grown at 200 oC showed nanoparticles (NPs) composedmicro-particles (MPs) like surfacemorphology and exhibited hexagonal crystal structures having a preferential orientation of (002). However, these structures have polycrystalline nature and zinc deficient chemical composition. Raman spectroscopic analyses reveal that the as-deposited ZnOMPs structures at 200 oC have compressive stress and strong polar lattice bonds. The optical studies showthat these ZnO structures are highly transparent (92%) in visible region and contain a direct optical band gap of about 3.42 eV.