Yi-Fei Zhang, Jiang Shao, Hao Dong, Guangxu Lan, Ya-Wen Zhang
Reporting a facet-regulated CeO2 catalyst that preferentially exposes vacancy-derived frustrated Lewis pair (FLP) sites on the (100) surface for highly efficient and selective ERA of 5-HMF with ethanolamine. The optimized catalyst delivers 100% HEMF selectivity and a Faradaic efficiency of 99% at a current density of 20 mA cm-2. Vacancy-derived FLP sites are the key catalytic motifs for selective ERA and identify vacancy configuration engineering as an effective strategy for the rational design of highly efficient CeO2 electrocatalysts.
Electrocatalytic construction of C─N bonds from biomass-derived platform molecules offers a sustainable route to value-added nitrogen-containing chemicals. In particular, the electrocatalytic reductive amination (ERA) of 5-hydroxymethylfurfural (5-HMF) with ethanolamine provides a green alternative to conventional reductive amination by circumventing the use of high-pressure H2 and stoichiometric chemical reductants. Herein, we report a facet-regulated CeO2 catalyst that preferentially exposes vacancy-derived frustrated Lewis pair (FLP) sites on the (100) surface, enabling highly efficient and selective ERA to produce 2-[(5-(hydroxymethyl)furan-2-yl)methylamino]ethanol (HEMF). The optimized catalyst delivers 100% HEMF selectivity and a Faradaic efficiency of 99% at a current density of 20 mA cm-2. Electrochemical measurements, high-resolution transmission electron microscopy, temperature-programmed desorption, and in situ ATR-SEIRAS reveal that the vacancy-derived FLP sites promote the cooperative adsorption of the imine intermediate and activation of its C═N bond, thereby highlighting the decisive role of vacancy configuration in governing catalytic performance. These findings establish vacancy-derived FLP sites as the key catalytic motifs for selective ERA and identify vacancy configuration engineering as an effective strategy for the rational design of highly efficient CeO2 electrocatalysts.