H₂ Storage in Li₃N. Temperature-Programmed Hydrogenation and Dehydrogenation

Hydrogen storage in Li 3 N was investigated via temperature-programmed hydrogenation (TPH) and temperature-programmed dehydrogenation (TPD). TPH spectra indicated an initial hydrogenation temperature of Li 3 N of ∼150 °C, 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 °C. The maximum amount of low-temperature released H 2 corresponding to the two peaks at 240 and 270 °C was 6.0 wt %. XRD indicated that most of the low-temperature released hydrogen can be attributed to the transformation of LiNH 2 to Li 2 NH. The amount and properties of the releasable hydrogen are also dependent on the duration and temperature of the Li 3 N hydrogenation.