title: Thermally stable N2-intercalated WO3 photoanodes for water oxidation.
abstract: We describe stable intercalation compounds of the composition xN(2)·WO(3) (x = 0.034-0.039), formed by trapping N(2) in WO(3). The incorporation of N(2) significantly reduced the absorption threshold of WO(3); notably, 0.039N(2)·WO(3) anodes exhibited photocurrent under illumination at wavelengths ≤640 nm with a faradaic efficiency for O(2) evolution in 1.0 M HClO(4)(aq) of nearly unity. Spectroscopic and computational results indicated that deformation of the WO(3) host lattice, as well as weak electronic interactions between trapped N(2) and the WO(3) matrix, contributed to the observed red shift in optical absorption. Noble-gas-intercalated WO(3) materials similar to xN(2)·WO(3) are predicted to function as photoanodes that are responsive to visible light.
authors.affiliation: Beckman Institute, Division of Chemistry and Chemical Engineering, California Institute of Technology, M/C 127-72, 1200 East California Boulevard, Pasadena, California 91125, USA.
authors.forename: Qixi
authors.initials: Q
authors.lastname: Mi
authors.forename: Yuan
authors.initials: Y
authors.lastname: Ping
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Bingfei
authors.initials: B
authors.lastname: Cao
authors.forename: Bruce S
authors.initials: BS
authors.lastname: Brunschwig
authors.forename: Peter G
authors.initials: PG
authors.lastname: Khalifah
authors.forename: Giulia A
authors.initials: GA
authors.lastname: Galli
authors.forename: Harry B
authors.initials: HB
authors.lastname: Gray
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Lewis