Essentially atomically smooth(100) and (110) n-TiO2 (rutile) surfaces were prepared by wet-method. The success in preparation of the atomically smooth and stable n-TiO2 surfaces enabled us to reveal clear crystalface dependences of the surface band edges, hole reactivity and various kinds of photo-induced reactions in aqueous solutions. This paper reviews our research of photoelectrochemical properties of single crystal TiO2 surfaces.
