title: Band structure engineering of anatase TiO2 by metal-assisted P-O coupling.
abstract: In this work, we demonstrate that the metal-assisted P-O coupling is an effective approach to improve the photoelectrochemical properties of TiO2. The (Sc + P) and (In + P) codoping effects on electronic structures and photocatalytic activities of anatase TiO2 are examined by performing hybrid density functional theory calculations. It is found that the coupling of P dopant with the second-nearest neighboring O atom assisted by acceptor metals (Sc/In) leads to the fully occupied and delocalized intermediate bands within the band gap of anatase TiO2, which is driven by the P-O antibonding states (π*). This metal-assisted P-O coupling can prevent the recombination of photogenerated electron-hole pairs and effectively reduce the band gap of TiO2. Moreover, the band edge alignments in (Sc + P) and (In + P) codoped anatase TiO2 are desirable for water-splitting. The calculated optical absorption curves indicate that (Sc + P) and (In + P) codoping in anatase TiO2 can also effectively enhance the visible light absorption.
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Jiajun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Qiangqiang
authors.initials: Q
authors.lastname: Meng
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Qunxiang
authors.initials: Q
authors.lastname: Li
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Jinlong
authors.initials: J
authors.lastname: Yang