Single-Atom Fe With Fe-N4f1structure Showing Superior Performances for Semi-Hydrogenation of Alkynol

Abstract

The design of non-noble metal single-atom catalysts (SACs) with superior performance for semi-hydrogenation of alkynol is remarkable but challenging. Herein, fluorine-tuned Fe SACs supported on N, F-codoped carbon (Fe1-NFC) with a Fe-N4F1 structure is successfully prepared via a camplexation method. The  F-doping can modulate the electronic structure of the metalloporphyrin-like active sites (Fe-N4), promoting the transfer of electrons from Fe atoms to F atoms to form electron-deficient Feδ+ species. As a result, the Fe1-NFC catalyst shows a remarkable activity for the semi-hydrogenation of 2-methyl-3-butyn-2-ol to 2-methyl-3-buten-2-ol under mild conditions, with a TOF of 9163 h–1 and a selectivity of 96% conversion, both much higher than that of the Fe SACs supported on N-doped carbon (Fe1-NC). Density functional theory (DFT) calculations reveal that the excellent catalytic activity and selecivity are attributed to the interfacial electronic effect of Fe species induced by axial F-doping, thereby enhancing the exothermic adsorption of alkynol on the Fe-N4F1 structures and accelerating the desorption of alkenol to against the overhydrogenation.

Keywords: Single-atomic Fe catalyst, alkynol semi-hydrogenation, heteroatom doping, DFT calculations