摘要
This paper reports the study of structure of oxide interface in Pt-Rh alloy by atom probe field ion microscope (AP-FIM) which is well suited for the study of atom distribution with atomic scale at the surface and interface of alloy. AP depth profiles show that oxide interface exist in the Pt-Rh alloy which consists of PtO, RhO, PtO2 and RhO2. The mechanism of oxidation of the alloy is considered as that first oxygen molecules adsorbed on-to the surface of alloy then dissociate into oxygen atoms (O2&rarr2O). Consequently oxygen atoms diffuse into interior through grain boundary forming oxide (M+O&rarrMO). When the concentration of oxygen continuously increases the dioxide (MO+O&rarrMO2) forms.
This paper reports the study of structure of oxide interface in Pt-Rh alloy by atom probe field ion microscope (AP-FIM) which is well suited for the study of atom distribution with atomic scale at the surface and interface of alloy. AP depth profiles show that oxide interface exist in the Pt-Rh alloy which consists of PtO, RhO, PtO2 and RhO2. The mechanism of oxidation of the alloy is considered as that first oxygen molecules adsorbed on-to the surface of alloy then dissociate into oxygen atoms (O2&rarr2O). Consequently oxygen atoms diffuse into interior through grain boundary forming oxide (M+O&rarrMO). When the concentration of oxygen continuously increases the dioxide (MO+O&rarrMO2) forms.
