Understanding the fundamentals of TiO2 surfacesPart II. Reactivity and surface chemistry of TiO2 single crystals

In order to promote the application of TiO2 in surface modification technologies, a detailed understanding of its structure and properties is necessary. For this reason, the reactivity and corresponding surface chemistry of stoichiometric and non-stoichiometric single crystals of titanium dioxide have been widely studied. In Part II of this review, special attention is paid to the role of individual surface sites and the effect of available charge on the adsorption processes on stoichiometric and reduced single crystal rutile and anatase surfaces. In addition, the most appropriate surface science methods used to study the surface chemistry of these surfaces are also highlighted. An understanding of the interaction of H2O and O2 with oxide surfaces is extremely important because these adsorbates form a de facto part of the environment in all technological applications. Moreover, they play an extraordinarily important role in the processes taking place in high-performance devices in the fields of energy, environment, and health. Consequently, special consideration is given to the adsorption and dissociation processes of the most technologically important inorganic adsorbates, such as H2O and O2, on model low Miller index single crystal surfaces of titania. In addition, light-induced reactivity of TiO2 and its application is also considered. Furthermore, the engineering of TiO2 nanocrystals with well-defined facets, their unusual photocatalytic properties, and applications are also briefly considered.