Preparation of Shape and Size-Controlled Zinc Oxide Nanostructures by Chemical Spray Pyrolysis Technique

ABSTRACTHighly structured layers comprising of vertically aligned zinc oxide rods, tripods or platelets were fabricated by spray pyrolysis method at temperatures of 510-550 °C. The zinc chloride solution was pulverized onto the preheated substrates of glass and ITO, SnO2, ZnO covered glass substrates with the help of compressed air as a carrier gas. ZnO layers were characterized by scanning electron microscopy and Raman spectroscopy. C-axis orientated ZnO nanorod arrays of well-developed hexagonal rods with length from some hundreds of nanometers up to some microns and with diameter from 70 nm up to 900 nm . The rise of both the growth temperature and solution concentration increases rod dimensions. Deposition of the solutions with the concentration of 0.05 up to 0.2 mol/l results in structured layers composed of rods on glass substrates. Using ITO, SnO2 and ZnO thin film covered glasses diluted solutions should be used to obtain ZnO nanorods. Alcoholic solutions allow deposit thinner rods and reduce the deposition temperature. Very strong and relatively narrow E2 Raman bands indicate that ZnO rods prepared by spray pyrolysis technique are of high crystal quality.