Nature of Ni and Cu Species in Reduced Bimetallic NiCu/Al₂O₃ Catalysts

What effect does the simultaneous presence of the elements nickel and copper in a hydrogenation catalyst have on the kind of species formed upon catalytic reduction? X‐ray photoelectron and Auger electron spectroscopy have been employed in an attempt to answer this question. Ni 0 , Ni 2⊕ , Cu 0 , and Cu ⊕ species were detected, Ni 0 increasing with the copper content and Cu 0 increasing with the nickel content.