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The solid reaction of lithium hydride and lithium hydroxide in lithium hydride pellet is first directly observed at normal ambient condition after 4 years storage. Layer-by-layer XPS results show that LiOH hydrolysis layer quickly forms on the LiH surface, LiOH reacts with bulk LiH to form Li2O and H2. Due to the great H2 outgassing after long time conservation, bubbling problem actually exists during the practical long-time preserving period. Using CO2 as pre-treatment gas during the LiH sample preparation process is a feasible way to prevent LiH sample from bubbling after long storage period. Moreover, Li2CO3 shows possible delay effect on the solid reaction of LiOH with LiH in this work, thus preserving LiH sample in CO2 containing atmosphere might also be an prospective way to protect the sample from further corrosion.

Uranium dioxide films were deposited on Si (1 1 1) substrates by dc magnetron sputtering method at different sputtering parameters. The structure, morphology and chemical state of the films were studied by field emission scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and atomic force microscopy. Influences of film thickness on the microstructure and optical properties were investigated. Experimental results show that the film crystallites are preferentially oriented with the (1 1 1) planes. The average grain size increases with increasing film thickness. AFM images show that the root mean square roughness of the films is between 1.2 nm and 2.1 nm. Optical constants (refractive index, extinction coefficient) of the films in the wavelength range of 350–1000 nm are obtained by ellipsometric spectroscopy. The result shows that the refractive index decreases with the increasing film thickness, while extinction coefficient increases with the film thickness.