Preparation and characterization of nanostructured ZnO thin films for photoelectrochemical splitting of water

Nanostructured zinc oxide thin films (ZnO) were prepared on conducting glass support (SnO2: F overlayer) via sol-gel starting from colloidal solution of zinc acetate 2-hydrate in ethanol and 2-methoxy ethanol. Films were obtained by spin coating at 1500 rpm under room conditions (temperature, 28-35A degrees C) and were subsequently sintered in air at three different temperatures (400, 500 and 600A degrees C). The evolution of oxide coatings under thermal treatment was studied by glancing incidence X-ray diffraction and scanning electron microscopy. Average particle size, resistivity and bandgap energy were also determined. Photoelectrochemical properties of thin films and their suitability for splitting of water were investigated. Study suggests that thin films of ZnO, sintered at 600A degrees C are better for photoconversion than the films sintered at 400 or 500A degrees C. Plausible explanations have been provided.