Rhodium(0), Ruthenium(0) and Palladium(0) nanoparticles supported on carbon-coated iron: Magnetically isolable and reusable catalysts for hydrolytic dehydrogenation of ammonia borane

We report the synthesis of magnetically isolable ruthenium(0), rhodium(0), and palladium(0) nanoparticles, supported on carbon-coated magnetic iron particles, and their employment as catalysts in hydrolysis of ammonia borane. Carbon-coated iron (C-Fe) particles are obtained by co-processing of iron powders with methane in a radio frequency thermal plasma reactor. The impregnation of ruthenium(III), rhodium(III) and palladium(II) ions on the carbon-coated iron particles followed by aqueous solution of sodium borohydride leads to the formation of respective metal(0) nanoparticles supported on carbon coated iron, M-0/C-Fe NP (M 1/4 Ru, Rh, and Pd) at room temperature. M-0/C-Fe NPs are characterized using the ICP-OES, XPS, TEM, and EDX techniques and tested as catalysts for hydrolysis of ammonia borane at 298 K. The results reveal that Rh-0/C-Fe, Ru-0/C-Fe, Pd-0/C-Fe catalysts provide turnover frequency of 83, 93, and 29 min(-1), respectively, in this industrially important reaction. More importantly, these magnetically separable metal(0) nanoparticles show very high reusability with no noticeable activity loss in subsequent runs of hydrolysis evolving 3.0 equivalent H-2 per mole of ammonia borane. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

Magnetic isolable ruthenium(0), rhodium(0), and palladium(0) nanoparticles supported on carbon-coated iron particles were synthesized and used as catalysts for hydrolysis of ammonia borane. The catalysts demonstrated high reactivity and turnover frequency at room temperature, showing great potential for industrial applications.