title: Reactivity of oxygen deficient cerium oxide clusters with small gaseous molecules.
abstract: Oxygen deficient cerium oxide cluster ions, Ce(n)O(m)(+) (n = 2-10, m = 1-2n) were prepared in the gas phase by laser ablation of a cerium oxide rod. The reactivity of the cluster ions was investigated using mass spectrometry, finding that oxygen deficient clusters are able to extract oxygen atoms from CO, CO2, NO, N2O, and O2 in the gas phase. The oxygen transfer reaction is explained in terms of the energy balance between the bond dissociation energy of an oxygen containing molecule and the oxygen affinity of the oxygen-deficient cerium oxide clusters, which is supported by DFT calculations. The reverse reaction, i.e., formation of the oxygen deficient cluster ions from the stoichiometric ones was also examined. It was found that intensive heating of the stoichiometric clusters results in formation of oxygen deficient clusters via Ce(n)O(2n)(+) → Ce(n)O(2n-2)(+) + O2, which was found to occur at different temperatures depending on cluster size, n.
authors.affiliation: †Department of Basic Science, School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Nagata
authors.affiliation: †Department of Basic Science, School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Miyajima
authors.affiliation: ‡Department of Chemistry, The University of Adelaide, Adelaide, South Australia 5005, Australia.
authors.forename: Robert Allan
authors.initials: RA
authors.lastname: Hardy
authors.affiliation: ‡Department of Chemistry, The University of Adelaide, Adelaide, South Australia 5005, Australia.
authors.forename: Gregory F
authors.initials: GF
authors.lastname: Metha
authors.affiliation: †Department of Basic Science, School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan.
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Mafuné