title: Role of point defects on the reactivity of reconstructed anatase titanium dioxide (001) surface.
abstract: The chemical reactivity of different surfaces of titanium dioxide (TiO2) has been the subject of extensive studies in recent decades. The anatase TiO2(001) and its (1 × 4) reconstructed surfaces were theoretically considered to be the most reactive and have been heavily pursued by synthetic chemists. However, the lack of direct experimental verification or determination of the active sites on these surfaces has caused controversy and debate. Here we report a systematic study on an anatase TiO2(001)-(1 × 4) surface by means of microscopic and spectroscopic techniques in combination with first-principles calculations. Two types of intrinsic point defects are identified, among which only the Ti(3+) defect site on the reduced surface demonstrates considerable chemical activity. The perfect surface itself can be fully oxidized, but shows no obvious activity. Our findings suggest that the reactivity of the anatase TiO2(001) surface should depend on its reduction status, similar to that of rutile TiO2 surfaces.
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.forename: Huijuan
authors.initials: H
authors.lastname: Sun
authors.forename: Shijing
authors.initials: S
authors.lastname: Tan
authors.forename: Hao
authors.initials: H
authors.lastname: Feng
authors.forename: Zhengwang
authors.initials: Z
authors.lastname: Cheng
authors.forename: Jin
authors.initials: J
authors.lastname: Zhao
authors.forename: Aidi
authors.initials: A
authors.lastname: Zhao
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Luo
authors.forename: Jinlong
authors.initials: J
authors.lastname: Yang
authors.forename: J G
authors.initials: JG
authors.lastname: Hou
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