LiH‐Destabilized Melamine for a Room‐Temperature Ammonia‐Free Hydrogen Evolution Reaction

Abstract

AbstractThe interaction between protic hydrogen (H+) and hydridic hydrogen (H−) species gives rise to H2 and spawns the establishment of metal‐N−H hydrogen storage material systems. N‐based compounds such as metal amides (M−NH2) have shown viability for protic H generation. In this preliminary research, we adopted a chemical reaction approach using a hydrogen‐enriched quasi‐aromatic tri‐amide “melamine (C3H6N6)” as protic H feedstock and lithium hydride (LiH) as the hydridic H‐based destabilizer aiming at expanding metal and organic substrates and developing new metalorganic hydride materials. The dehydrogenation kinetics and reaction pathways of C3H6N6−xLiH (x=1, 3 or 6) composites on heating and ball‐milling conditions were investigated in detail. The results showed that C3H6N6−LiH consisting of a 1/6 mole ratio can evolve 6.6 wt % H2 (approximately 5.75 equiv. H2) at room temperature through mechanochemical method of ball‐milling. Interestingly, it showed different reaction paths under heating, C3H6N6−6LiH composite could release 2.87 wt % hydrogen under 210 °C and transform into a CN heterocyclic intermediate structure examined by NMR, FTIR, XRD, and Raman characterizations.