title: Polyoxometalate grafting onto silica: stability diagrams of H3PMo12O40 on {001}, {101}, and {111} β-cristobalite surfaces analyzed by DFT.
abstract: The process of grafting H(3)PMo(12)O(40) onto silica surfaces is studied using periodic density functional theory methods. For surfaces with a high hydroxyl coverage, the hydroxyl groups are consumed by the polyoxometalate protons, resulting in water formation and the creation of a covalent bond between the polyoxometalate and the surface, and mostly no remaining acidic proton on the polyoxometalate. When the surfaces are partially dehydroxylated and more hydrophobic, after temperature pretreatment, less covalent and hydrogen bonds are formed and the polyoxometalate tends to retain surface hydroxyl groups, while at least one acidic proton remains. Hence the hydroxylation of the surface has a great impact on the chemical properties of the grafted polyoxometalate. In return, the polyoxometalate species affects the compared stability of the partially hydroxylated silica surfaces in comparison with the bare silica case.
authors.affiliation: Université de Lyon, Institut de Chimie de Lyon, CNRS, Ecole Normale Supérieure de Lyon, Laboratoire de Chimie, 46 Allée d'Italie, 69046 Lyon, France. xavier.rozanska@ens-lyon.fr
authors.forename: Xavier
authors.initials: X
authors.lastname: Rozanska
authors.forename: Philippe
authors.initials: P
authors.lastname: Sautet
authors.forename: Françoise
authors.initials: F
authors.lastname: Delbecq
authors.forename: Frédéric
authors.initials: F
authors.lastname: Lefebvre
authors.forename: Sergei
authors.initials: S
authors.lastname: Borshch
authors.forename: Henri
authors.initials: H
authors.lastname: Chermette
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Basset
authors.forename: Eva
authors.initials: E
authors.lastname: Grinenval