Aqueous hydrazine borane N2H4BH3 and nickel-based catalyst: An effective couple for the release of hydrogen in near-ambient conditions

Nickel-based bimetallic catalysts were screened using the sodium borohydride NaBH4 hydrolysis and the aqueous hydrazine borane N2H4BH3 dehydrogenation. A total of 22 bimetallic catalysts were synthesized according to an easy process while focusing on metals like Fe, Co, Ni, Cu, Rh, Pd, Ag, Ir, Pt and Au. In the end, the bimetallic candidate Ni87.5Pt12.5 showed to be the most active and the most selective for the dehydrogenation of N2H4BH3. At 70 degrees C, it is able to decompose N2H4BH3 into 5.8 equivalents of H-2+N-2 in less than 12 min such as: N2H4BH3 + 3H(2)O -> 0.95 N-2 + 0.1 NH3 + B(OH)(3) 4.85H(2). Durability and stability tests were also performed. In our conditions, Ni87.5Pt12.5 was found to suffer from small loss of performance because of an electronic evolution of the catalytic surface leading to modified sorption properties of the catalytic sites. Our main results are reported and discussed herein. (C) 2017 Energy Institute. Published by Elsevier Ltd. All rights reserved.