Hydrogen generation rate enhancement by in situ Fe(0) and nitroarene substrates in Fe_3O_4@Pd catalyzed ammonia borane hydrolysis and nitroarene reduction tandem reaction

摘要

We report the catalytic enhancement of hydrogen generation by 1) in situ Fe(0) formed and 2) nitroarenes substrates during Fe3O4@Pd core-shell nanoparticles catalyzed tandem reaction. The active hydrogen species are generated in Pd shell, which either combine to form H-2 gas or take part in relatively faster nitroarene reduction reaction. The rate of hydrogen generation from ammonia borane is dependent on the nitroarene substrate and is higher when 4-nitrophenol is used. This is due to the difference in ammonia borane adsorption on the surface of the catalyst. During recyclability, the H-2 generation rate of 2 wt% Pd loaded samples is higher than other compositions. Such an enhancement has been attributed to the formation of Fe(0) via gamma-FeOOH mediated by Pd species, presumably through Pd(OH)(2). The electronic connection between Fe and Pd interface is thus shown to play an important role in the catalytic enhancement of the tandem reaction. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.