Nanoporous Ni-based catalysts for hydrogen generation from hydrolysis of ammonia borane

• Facile synthesis of nanoporous Ni, Ni–Fe, NiPt.
• Catalytic hydrolysis of ammonia borane by Ni-based nanoparticles.
• High activity of Ni0.99Pt0.01 catalyst with low Pt loading.

We report nanoporous Ni, Ni–Fe, and Ni–Pt as catalysts for hydrogen generation from hydrolytic dehydrogenation of ammonia borane (NH3BH3, AB). The Ni and Ni–Fe nanoparticles with diameters of 20–25 nm were synthesized by a colloidal method in starch-containing aqueous solution. They exhibited considerable in situ catalytic performance but severely lost activity after separating from the reaction solution. Nanoporous Ni1−xPtx (x = 0.01, 0.08 and 0.19) with particle size below 5 nm was prepared from the isolated Ni nanoparticles through a replacement reaction. After centrifugation, drying, washing, and annealing, the obtained nanoporous Ni–Pt could attain remarkable activity, high hydrogen generation rate and efficiency, and low activation energy.