X-Ray Photoelectron Spectra of Aluminum Alloys and Their Anodic Oxide Films

Abstract

Binding energies of the elements in binary aluminum alloys and their anodic oxide films formed in sulfuric acid solution under a constant current density were studied by X-Ray photoelectron spectroscopy. The results obtained were as follows. (1) The binding energies of Al_2P, Al_2S, and O_1S electrons in aluminum alloys and thier oxide films were nearly identical with those in high purity aluminum and its oxide film, respectively. (2) The binding energies of Mg_2P electrons in Al-10% Mg alloy and its oxide films were estimated to be 50.9eV, which was found to be about 1.0eV higher than the binding energy at Mg_2P electron for MgO and the oxide found in the spectrum of the Mg metal. The tendency for this energy shift was also clearly found in the spectrum of MgKL₃L₃ Auger electron. (3) The spectra of Si_2P electrons in Al-3% Si alloy and its oxide films were not clearly detected by the interferences of the spectrum of plasma loss due to the emission of Al_2P electron and by the spectrum of Al_{Kα3, 4} X-Ray lines at Al_2S electron.