New and modern nanoscience developments bring new nanomaterials with unique electronic and optical properties that are of outmost importance in modern applications. This book presents the spray pyrolysis technique that is used to produce thin films of metallic oxides on glass substrates. Also discussed are the process variables of the spray pyrolysis process used to manufacture specific structures such as nanostructured thin films. Building on the foundation set by the pyrolysis technology, several metallic oxides have been synthesized and characterized. The focus of research is on the linkage between the synthesis of binary oxides such as ZnO, In2O3, TiO2, and MoO3, physical characterization and the effects of doping on their properties. This book provides interesting insights into the literature on applied research, and each chapter contains details that aim to develop awareness of the topic and the physicochemical methods used, including the nanostructure, optical and electrical features. The four chapters present and discuss several comprehensive studies of metallic oxides for various applications, such as water purification, optoelectronic devices, photocatalysts, etc and give the research community and students the thorough grounding they need in spray pyrolysis applications in the nanotechnology of metal oxides.