H2 storage in Li3N.: Temperature-programmed hydrogenation and dehydrogenation

Hydrogen storage in Li3N was investigated via temperature-programmed hydrogenation (TPH) and temperature-programmed dehydrogenation (TPD). TPH spectra indicated an initial hydrogenation temperature of Li3N of similar to150 degreesC, independent of the H-2 partial pressure even below 0.5 atm. However, the increase in H-2 partial pressure accelerated the hydrogenation rate. The TPD curves exhibited three H-2 peaks located at 240, 270, and above 380 degreesC. The maximum amount of low-temperature released H-2 corresponding to the two peaks at 240 and 270 degreesC was 6.0 wt %. XRD indicated that most of the low-temperature released hydrogen can be attributed to the transformation of LiNH2 to Li2NH. The amount and properties of the releasable hydrogen are also dependent on the duration and temperature of the Li3N hydrogenation.