Dataset of Mechanically stimulated gas emission from pellets of sodium alanate subjected to rubbing at room temperature under vacuum and related surface, structural, mechanical, and tribological characterization of the pellets

Datasets of mass-spectrometry signals were obtained in the experiments with non-thermal dehydrogenation of sodium alanate through the application of mechanical energy. An application of mechanical energy was explored as a new non-thermal method to drive H2 emission from undoped sodium alanate at room temperature. Dehydrogenation reactions were studied on a micrometer scale using localized rubbing under ultrahigh vacuum. Mechanically Stimulated Gas Emission Mass-Spectrometry (MSGE-MS) including the Dynamic gas expansion method was used to determine the kinetic parameters of hydrogen emission as well as the composition and emission behaviour of trace gases. It was found that mild rubbing of NaAlH4 pellets under vacuum led to intensive and almost instantaneous gas emission. The dominating species in the emitted gases was H2 (>99%). Traces (~0.1%) of mono- and polyalanes, NaAlH4 vapours, CO2 and other no identified gases were registered. Several H2 emission modes, which characteristic time constants ranged widely from 0.6 to 465 s, were observed. None of the dehydrogenation reactions involved could be connected to either the thermal effect of friction or the direct coupling of mechanical forces to the energy landscape of chemical reactions. The study was complemented by structural, morphological, tribological, mechanical and surface analyses. It was suggested that the tribochemical reactions can be triggered by plastic deformation and shearing.