Visible light photo-oxidation of model pollutants using CaCu3Ti4O12: an experimental and theoretical study of optical properties, electronic structure, and selectivity.

ABSTRACT: Charge transfer between metal ions occupying distinct crystallographic sublattices in an ordered material is a strategy to confer visible light absorption on complex oxides to generate potentially catalytically active electron and hole charge carriers. CaCu3Ti4O12 has distinct octahedral Ti4+ and square planar Cu2+ sites and is thus a candidate material for this approach. The sol−gel synthesis of high surface area CaCu3Ti4O12 and investigation of its optical absorption and photocatalytic reactivity with model pollutants are reported. Two gaps of 2.21 and 1.39 eV are observed in the visible region. These absorptions are explained by LSDA+U electronic structure calculations, including electron correlation on the Cu sites, as arising from transitions from a Cu-hybridized O 2p-derived valence

SUBMITTER: Clark JH 

PROVIDER: S-EPMC3216362 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature