A significant enhancement of catalytic activity in Pt/Fe2O3 catalysts via L-histidine decoration for better catalytic hydrogenation performance

Chemoselective hydrogenation of cinnamaldehyde is an important reaction for preparation of high value-added chemicals. Thermodynamic disadvantage makes it difficult to prepare cinnamyl alcohol under mild conditions. Thus, preparation of Pt dominant heterogenous catalysts with improved catalytic activity and stability has attached significant importance for solving this problem. In this paper, L-histidine (His) decorated Fe2O3 material was employed to support Pt nanoparticles and fabricate Pt/His-Fe2O3 catalyst with high catalytic activity. The presence of L-histidine greatly improved interfacial effect between Pt nanoparticles and His-Fe2O3 carrier, which not only effectively promoted its dispersion, but also brought better mass transfer between Pt nanoparticles and cinnamaldehyde. Therefore, it showed high catalytic performance with 92.4% cinnamaldehyde conversion and 90.4% selectivity to cinnamyl alcohol at 60 °C. Besides, this catalyst exhibited high catalytic stability and slight fluctuations in catalytic efficiency were observed after five cycle tests. In substrate-extending hydrogenation tests, the Pt/His-Fe2O3 catalyst also presented high applicability in chemoselective hydrogenation of a, β-unsaturated aldehydes and achieved higher selectivity toward unsaturated alcohols. Thus, this work provides a facile and effective approach for designing high-performance Pt based heterogenous catalysts with L-histidine decoration for enhanced chemoselective hydrogenation of cinnamaldehyde.