| Abstract
| - Cu−Pd/Al2O3 bimetallic catalysts have been characterized by XRD, TEM, and EDX techniques. The surfacestructure has been investigated by FT-IR spectroscopy of low-temperature adsorbed CO in the reduced and in theoxidized state. Evidence has been provided of the formation of Cu−Pd alloy nanoparticles, both of the α-phase(disordered fcc) and of the β-phase (ordered CsCl-type). IR spectra suggest that Cu likely decorates the edges whilePd mostly stays at the main faces. Part of copper disperses as Cu+ on the support even after reduction. The presenceof copper seems to modify strongly the sate of oxidized Pd centers in oxidized high-Pd content materials. The redoxchemistry of the system, where Pd is reduced more easily than Cu, appears to be very complex.
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