Hydrogen release and uptake in the Li–Zn–N system

• Reactions of ZnCl2 + nLiNH2 gave a mixture of Zn3N2 and LiZnN as products.
• No stable amide chloride, imide chloride or nitride chloride phases were identified.
• The addition of lithium hydride (LiH) changed the main gaseous product from NH3 to H2.
• Neither pure LiZnN nor Zn3N2 could be rehydrogenated under the conditions studied.
• LiZnN/Zn3N2, and LiZnN/LiCl mixtures hydrogenated at 300 °C to form LiNH2 and Zn metal.

Reactions of ZnCl2 + nLiNH2 at a range of molar ratios and temperatures gave a mixture of Zn3N2 and LiZnN as products; no stable amide chloride, imide chloride or nitride chloride phases were identified. Temperature-programmed desorption with mass spectrometry (TPD–MS) showed that the main gas emitted was ammonia (NH3). The addition of lithium hydride (LiH) changed the main gaseous product from NH3 to H2, which was released at a low temperature beginning around 90 °C. Neither pure LiZnN nor Zn3N2 could be rehydrogenated under the conditions studied. However, mixtures of LiZnN and Zn3N2, and LiZnN and LiCl reacted with H2 at 300 °C to form LiNH2 and zinc metal.