Zinc Oxide Thin Films Grown by Aerosol Assisted CVD

Zinc oxide (ZnO) thin films are deposited at 400-650 degrees C onto glass substrates by aerosol assisted (AA)CVD of a zinc acetate [Zn(C2H3O2)(2)] solution in methanol. The thin films show high transparency over the visible and infrared regions (80-95%) and a 001 (c-axis) preferred orientation. The surface morphology and crystallographic orientation are dependent on the substrate temperature. The photocatalytic activity of the films is determined using the destruction of stearic acid (SA) by UV irradiation. The rate is monitored via infrared spectroscopy (IRS) and shows appreciable activity, close to that seen for anatase titania, in the films deposited at 650 degrees C. Water droplet contact angles on both ambient and UV-irradiated ZnO surfaces are determined, and there is seen to be an increase in photoinduced hydrophillicity for all films, with a reduction in contact angle of around 50 degrees.