Thermal degradation analysis of deuterium-ion-implanted V₂₅Cr₄₀Ti₃₅ using synchrotron radiation photoelectron spectroscopy

Abstract

The thermal degradation of a native oxide layer on the hydrogen storage alloy V₂₅Cr₄₀Ti₃₅ and the thermal desorption property of deuterium molecules were studied by synchrotron radiation soft X-ray photoelectron spectroscopy and thermal desorption mass spectrometry. Photoelectron spectra of O-1s, C-1s, V-2p, Cr-2p, and Ti-2p were observed for an as-received sample and a deuterium-ion-implanted one. Although the oxide layer changed dramatically by thermal annealing between 373 K and 473 K for the un-implanted sample, the change of the deuterium-ion-implanted sample was lying between 473 K and 573 K corresponding to D₂ desorption. The implantation of deuterium resulted in the stabilization of the surface oxide layer by approximately 100 deg.