- Email: [email protected]
Adsorption and dissociation of oxygen molecules on palladium (110) surfaces at low temperatures
A362 155
Surface Science 217 (1989) 155-166 North-Holland, Amsterdam ADSORPTION AND DISSOCIATION OF OXYGEN MOLECULES O N P A I J , A D I U M (110) S U R F A C E S A T L O W T E M P E R A T U R E S Tatsuo MATSUSHIMA Research Institute for Catalysis, Hokkaido University, Sapporo 060, Japan Received 9 December 1988; accepted for publication 3 February 1989
The adsorption and dissociation of oxygen molecules were studied on palladium (110) surfaces at low temperatures by using thermal desorption combined with isotope tracer and low energy electron diffraction. Around 110 K, part of the admolecules dissociates and yields sites for molecular adsorption. The degree of both dissociations during exposure at 110 K and subsequent thermal desorption were estimated. New molecular adsorption was found on surfaces covered with a c(2 x 4)-0 lattice.
167
Surface Science 217 (1989) 167-178 North-Holland, Amsterdam XPS INVEb-~GATION OF THE OXIDATION OF THE Al/Pd INTERFACE: THE AI203/Pd INTERFACE P. L i ~ G A R E , F. F I N C K , R. R O C H E
* and G. MAIRE
Laboratoire de Catalyse et Chimie des Surfaces, UA CNRS 423, Unioersit~ Louis Pasteur, 4 rue Blaise Pascal, F-67070 Strasbourg Cede& France Received 17 May 1988; accepted for publication 28 February 1989 We have followed the oxidation of a polycrystalline Pd sample coated with thin aluminum fdms. The resulting overlayer was composed essentially of an AI203 overla3q~r coating the Pd substrate. At low AI doses, the very first layer was formed by PdO. Unlike 3D PdO, thh Pd oxide exhibits partial decomposition under UHV at room temperature. Moreover, in all the cases examined here, our photoemission results could he explained only by the existence of small Pd aggregates included in the AI203 matrix. These dusters revealed several features of their electronic state: the Pd core levels exhibited a surface-like behaviour and their work function appeared to be lower than that of the Pd substrate, depending on their size.
Surface Science 217 (1989) 155-166 North-Holland, Amsterdam ADSORPTION AND DISSOCIATION OF OXYGEN MOLECULES O N P A I J , A D I U M (110) S U R F A C E S A T L O W T E M P E R A T U R E S Tatsuo MATSUSHIMA Research Institute for Catalysis, Hokkaido University, Sapporo 060, Japan Received 9 December 1988; accepted for publication 3 February 1989
The adsorption and dissociation of oxygen molecules were studied on palladium (110) surfaces at low temperatures by using thermal desorption combined with isotope tracer and low energy electron diffraction. Around 110 K, part of the admolecules dissociates and yields sites for molecular adsorption. The degree of both dissociations during exposure at 110 K and subsequent thermal desorption were estimated. New molecular adsorption was found on surfaces covered with a c(2 x 4)-0 lattice.
167
Surface Science 217 (1989) 167-178 North-Holland, Amsterdam XPS INVEb-~GATION OF THE OXIDATION OF THE Al/Pd INTERFACE: THE AI203/Pd INTERFACE P. L i ~ G A R E , F. F I N C K , R. R O C H E
* and G. MAIRE
Laboratoire de Catalyse et Chimie des Surfaces, UA CNRS 423, Unioersit~ Louis Pasteur, 4 rue Blaise Pascal, F-67070 Strasbourg Cede& France Received 17 May 1988; accepted for publication 28 February 1989 We have followed the oxidation of a polycrystalline Pd sample coated with thin aluminum fdms. The resulting overlayer was composed essentially of an AI203 overla3q~r coating the Pd substrate. At low AI doses, the very first layer was formed by PdO. Unlike 3D PdO, thh Pd oxide exhibits partial decomposition under UHV at room temperature. Moreover, in all the cases examined here, our photoemission results could he explained only by the existence of small Pd aggregates included in the AI203 matrix. These dusters revealed several features of their electronic state: the Pd core levels exhibited a surface-like behaviour and their work function appeared to be lower than that of the Pd substrate, depending on their size.