Defects probing and effects in oxide films and nanostructures

Oxide-based films and nanostructures have emerged as important and promising materials for a wide range of applications such as photovoltaics, photocatalysis, optoelectronics, gas sensing and electronics. A common feature unifies these application fields which is related to the structural defects of these materials and strongly affects their functionality. To develop an appropriate understanding of the properties of these oxides, it is necessary to address the material preparation methods and defect probing issues. This work deals with oxide films and nanostructures synthesis processes, their stoichiometry control and defect identifying, in relation with their electronic, electrical and optical properties. Titanium, zinc and zirconium oxide-based materials are considered. X-ray diffraction, x-ray photoelectron, positron annihilation and UV-Vis-NIR spectroscopies are employed for the structure and defect study