International Journal of Hydrogen Energy, Vol.45, No.3, 1649-1657, 2020
Novel cake-like Fe-N-C hybrid for H-2 activation
The activation and utilization of hydrogen energy is an effective method to solve the global energy crisis and environmental pollution. Herein, biomass-derived Fe-N-C catalysts for H-2 activation were synthesized via the imitation of sponge cake baking. The sample pyrolyzed at 500 degrees C (Fe-N-C-500) presented the well-defined cake-like architecture with uniform distribution of Fe3O4 nanoparticles (NPs). Doping N species dispersed around metallic NPs in high density. Fe-N-C-500 exhibited excellent performance in the catalytic hydrogenation of nitrobenzene. The activity of Fe-N-C-500 depended on Fe3O4 NPs and pyridinic N, rather than Fe-N. The typical core-shell structure deemed vital for H-2 activation in previous reports was not necessary. Notably, water could significantly promote the H-2 activation, which might establish the communication between hydrogen molecules adsorbed on Fe3O4 NPs and doping N species through hydrogen bonds. Moreover, low temperature pyrolytic Fe-N-C-500 exhibited excellent stability and provided a promising potential for selective hydrogenation of nitroarenes or alkyne by regulating the reaction condition. This work provides an innovative approach to construct heterogeneous catalysts for H-2 activation. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.