Journal of the Chemical Society Faraday Transactions · 1995 · 60 citations · 12 references
Natural SciencesChemistryMaterials SciencePhysical ChemistrySurface ChemistrySurface ScienceAdsorption At InterfacesMineral Surface ChemistrySurface AdsorptionSurface PhysicsSurface SpectroscopyGas AdsorptionHydride FormationHydride Transfer ProcessesIn Situ SpectroscopyIn Situ Surface SpectroscopyMolecular Hydrogen FormationSurface DissociationZirconia
The interaction of hydrogen with ZrO2 at high temperatures (673–873 K) has been studied by using in situ FTIR spectroscopy. OH species are formed with O—H stretching frequencies at 3650 cm–1 on the surface of monoclinic and at 3730 cm–1 on the surface of tetragonal zirconia. The role of these hydroxy groups in the mechanism of hydrogen uptake and desorption at high temperatures, previously observed on monoclinic ZrO2, is discussed. According to our proposal, the nature of the hydrogen uptake of monoclinic zirconia consists of a heterolytic dissociation of molecular hydrogen and the simultaneous formation of OH species and hydridic species at adjacent O2– and Zr3+ surface sites.
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