Thermal absorption and desorption of deuterium in beryllium and beryllium oxide

Thermal desorption measurements have been made on high purity beryllium samples loaded with deuterium by thermal absorption in 13.3 kPa of D2 gas at 773 K. The saturation content of deuterium in the Be was determined to be 6.3 appm. Rutherford backscattering analysis indicated that the surface oxide grew significantly during the experiments, even in a vacuum of < 10−5 Pa. In order to determine deuterium solubility in BeO, a sample was oxidised in air for 16 h at 1073 K prior to deuterium loading. The deuterium content was estimated by 3He-D nuclear reaction analysis as approximately 200 appm. From attempts to fit previously published data using diffuson models, it is concluded that surface recombination is unlikely to be an important factor, whereas surface oxide and trapping effects significantly delay the release of deuterium from Be and BeO.