This book focuses on the progress in optoelectronic materials research and technologies, presenting reviews and original works on the theory, fabrication, characterization, and applications of optoelectronic materials. The chapters discuss preparation and properties of several optoelectronic materials, such as ZnO, SnO2, Zn1-XSnXO, BaTiO3, GaAs, GaP, ZnSe, and NaAlSi. The structural, optical, vibrational, and magnetic properties are discussed, in addition to transport and phase transformations.