Release of hydrogen from co-existing layers of carbon and beryllium with vacuum heating

Abstract

Carbon films containing hydrogen were prepared on quartz and Be plates by means of a plasma discharge in C 2H 4. Raman spectroscopy revealed that the carbon film on quartz was stable to heating in vacuo up to 800°C. On the other hand, X-ray diffraction measurements of the film prepared on the Be plates revealed that Be 2C was formed above 500°C. The intensity of the Be 2C peak increased with increasing temperature. Thermal desorption spectroscopy showed that hydrogen molecules were desorbed from the carbon films containing hydrogen by two different mechanisms. One is the reaction of C and adsorbed water to form H 2 and CO at around 400°C, and the other is the reaction of C and Be to form H 2 and Be 2C above 500°C.