Oxygen Sensitivity of Intermetallic Compound Surface Comprising Early Transition Metal

Abstract

Pd-based intermetallic compounds having early transition metals (Pd₃M; M = Nb, Ti, and Zr) prepared by arc melting were characterized by X-ray photoelectron spectroscopy. When the ingot of Pd₃Zr was ground in N₂ with an oxygen concentration below 1 ppb, a large part of the surface maintained its original intermetallic state; however, for Pd₃Nb and Pd₃Ti, their surfaces were completely oxidized even in the N₂ atmosphere. This indicates the remarkably high oxygen sensitivity of the intermetallic compounds with early transition metal.