Hydrogen generation and stoichiometric hydrolysis of core–shell Al-Li-NaBH4 composite

Abstract

Hydrogen energy has attracted considerable attention as a promising alternative to petroleum. Herein, a novel (Al–x%Li)–y%NaBH4 composite with a core–shell structure has been designed and synthesized by a one-step ball-milling method for generating hydrogen by hydrolysis. NaBH4 formed a surface coating that completely wrapped the Al–x%Li alloy particles to prevent agglomeration and oxidation. Meanwhile, the synergism between the Al–Li alloy and NaBH4 promoted the hydrogen generation rate (HGR) of the composite. The total hydrogen release content of (Al–10%Li)–10%NaBH4 reached 1468.8 mL·g−1, with the highest HGR reaching 4393.7 mL·g−1·min−1 at 303 K. The (Al–x%Li)-y%NaBH4 composites also exhibited outstanding hydrolysis capacity during reaction with a near-stoichiometric amount of added CoCl2 solution. The hydrogen emission exceeded 90% when only twice the amount of stoichiometric CoCl2 solution was injected. The hydrogen mass density of the total system increased to more than 2.3 wt% from approximately 0.6 wt% with the addition of 10 stoichiometric solution, indicating the practical application of the portable fuel cell in conserving the total volume of the facility.