Lithium nitride for reversible hydrogen storage

In this paper, we examined the basic properties in the 1:1 mixture of lithium amide LiNH₂ and lithium hydride LiH as a candidate of reversible hydrogen storage materials. The thermal desorption mass spectra of the ball milled mixture without any catalysts indicated that hydrogen H ₂ is released in the temperature range from 180 to 400°C while emitting a considerable amount of ammonia NH₃. On the other hand, the ball milled mixture containing a small amount of TiCl₃ as a catalyst showed the most superior hydrogen storage properties among the 1:1 mixtures with a small amount of catalysts, Ni, Fe, Co metals and TiCl ₃ (1 mol.%). That is, the product desorbs a large amount of hydrogen (∼5.5 wt.%) in the temperature from 150 to 250°C under the condition of a heating rate of 5°C/min, but it does not desorb ammonia at all within our experimental accuracy. In addition, we confirmed that the product shows an excellent cycle retention with an effective hydrogen capacity of more than 5 wt.% and a high reaction rate until at least 3 cycles.