Mixed HO/H plasma-induced redox reactions of thin uranium oxide films under UHV conditions.

X-ray photoelectron spectroscopy (XPS) has been used to study the effect of mixed HO/H gas plasma on the surfaces of UO, UO and UO thin films at 400 °C. The experiments were performed under ultra-high vacuum conditions. Deconvolution of the U4f peaks into U(IV), U(V) and U(VI) components revealed the surface composition of the films after 10 min plasma exposure as a function of H concentration in the feed gas of the plasma.