Application of defect chemistry for engineering of photosensitive oxide semiconductors

摘要

The present work considers the application of defect chemistry for engineering of semiconducting properties of metal oxides in general and TiO_2 in particular. The performance-related functional properties of TiO_2-based photoelectrode for hydrogen generation through water splitting using solar energy (solar-hydrogen) are considered in terms of (ⅰ) electronic structure, (ⅱ) charge transport, (ⅲ) near-surface charge distribution and the related electric fields, and (ⅳ) defect disorder of the outermost surface layer. The present work considers the modification of these functional properties for TiO_2 through the imposition of controlled defect disorder. The defect disorder is considered in terms of defect equilibria and the defect diagram describing the effect of oxygen activity on the concentration of both ionic and electronic defects.