Generation of surface steps on Pt(9 7 7) induced by the catalytic oxidation of CO

• Model catalyst: stepped Pt(9 7 7) surface that has monatomic array of steps.
• CO was oxidized to CO2 in a flow reactor near atmospheric pressure.
• Surface structure monitored with grazing X-ray diffraction in operando conditions.
• Monoatomic steps are generated or annihilated during reaction.
• Maximum step density occurs when the reaction rate is maximum.

The catalytic oxidation of CO has been investigated on the stepped Pt(9 7 7) surface at near ambient pressure and elevated temperature. It has been found that the reactivity is maximum at approximately the stoichiometric proportion of reactants and that surface monoatomic steps are generated by the reaction itself, being most abundant when the reaction proceeds with maximum efficiency.

The density of monatomic steps is highest when the reactants have the stoichiometric proportionsFigure optionsDownload high-quality image (44 K)Download as PowerPoint slide