title: Controlling the Electronic Structures of Perovskite Oxynitrides and their Solid Solutions for Photocatalysis.
abstract: Band-gap engineering of oxide materials is of great interest for optoelectronics, photovoltaics, and photocatalysis applications. In this study, electronic structures of perovskite oxynitrides, LaTiO2 N and SrNbO2 N, and solid solutions, (SrTiO3 )1-x (LaTiO2 N)x and (SrTiO3 )1-x (SrNbO2 N)x , are investigated using hybrid density functional calculations. Band gaps of LaTiO2 N and SrNbO2 N are much smaller than that of SrTiO3 owing to the formation of a N 2p band, which is higher in energy than the O 2p band. The valence- and conduction-band offsets of SrTiO3 /LaTiO2 N and SrTiO3 /SrNbO2 N are computed, and the adequacy for H2 evolution is analyzed by comparing the positions of the band edges with respect to the standard hydrogen electrode (SHE). The band gap of (SrTiO3 )1-x (LaTiO2 N)x and (SrTiO3 )1-x (SrNbO2 N)x solid solutions are also discussed.
authors.affiliation: Environmental Remediation Materials Unit, National Institute for Materials Science, Ibaraki, 305-0044, Japan. umezawa.naoto@nims.go.jp.
authors.forename: Naoto
authors.initials: N
authors.lastname: Umezawa
authors.affiliation: Department of Materials Science & Engineering, University of Delaware, Newark, DE, 19716, USA.
authors.forename: Anderson
authors.initials: A
authors.lastname: Janotti
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry* / Q000528:radiation effects; D002384:Catalysis; D007811:Lanthanum / Q000737:chemistry / Q000528:radiation effects; D008027:Light; D010087:Oxides / Q000737:chemistry* / Q000528:radiation effects; D055668:Photochemical Processes; D012996:Solutions; D013324:Strontium / Q000737:chemistry / Q000528:radiation effects; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D017610:Calcium Compounds; D010087:Oxides; D012996:Solutions; C059910:perovskite; D007811:Lanthanum; D014025:Titanium; D013324:Strontium
keywords: band gap; density functional theory; electronic structure; optoelectronics; solar energy conversion