Dehydrogenation of ammonia borane in fluoro alcohols

Dehydrogenation of ammonia borane was carried out in fluoro alcohol solvent in order to obtain compounds that are more likely candidates suitable for regeneration. Even though ammonia borane undergoes self-dissociation in 2,2,2-trifluoroethanol to liberate H2, decent hydrogen release rates were obtained by using Co–Co2B, Ni–Ni3B, and Co–Ni–B nanocomposites as catalysts. These catalysts are magnetic in nature and hence can be separated from the reaction mixture using a magnet for re-use. The final by-product NH4+ B(OCH2CF3)4− obtained after the catalytic dehydrogenation of ammonia borane was thoroughly characterized using 1H, 11B, and 13C NMR and IR spectroscopies. The FTIR data showed that the B–O bond in NH4+ B(OCH2CF3)4− is slightly weaker compared to boric acid. Preliminary investigations on the regenerative routes for ammonia borane from the by-product NH4+ B(OCH2CF3)4− showed indications of the formation of BNHx species.