Abstract: The length of time needed before hydriding is initiated on a uranium surface is often postulated to be determined by the thickness of its oxide layer. Here we used the introduction chamber of a X-ray photoelectron spectrometer (XPS) to initiate hydriding on a electropolished sample of 2.5 cm diameter after sputtering a 25 mm2 area in the XPS and transferring it back into the introduction chamber under ultra-high vacuum conditions. Contrary to expectations and a recent publication, hydriding occurred first in the un-sputtered area, and only very much later in the sputtered area.
Authors: W.J. Siekhaus and A.J. Nelson
Keywords: Uranium Hydride, Sputtering, XPS