Activity and segregation behavior of Pd75%Ag25%(1 1 1) during CO oxidation – An in situ NAP-XPS investigation
The surface reactivity during CO oxidation over Pd(1 1 1) and Pd75%Ag25%(1 1 1) single crystals has been investigated using near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) under excess oxygen conditions (p ≈ 2 mbar, O2:CO=10). The (√6×√6) Pd5O4 surface oxide is present on Pd(1 1 1) when the surface is highly active under the applied conditions. The CO2 formation profile follows a