Ti‐doped CeO₂ Stabilized Single‐Atom Rhodium Catalyst for Selective and Stable CO₂ Hydrogenation to Ethanol

Abstract

Development of effective and stable catalysts for CO 2 hydrogenation into ethanol remains a challenge. Herein, we report that Rh 1 /CeTiO x single-atom catalyst constructed by embedding monoatomic Rh onto Tidoped CeO 2 support has shown a super high ethanol selectivity ( � 99.1 %), record-breaking turnover frequency (493.1 h À 1 ), and outstanding stability. Synergistic effects of Ti-doption and monoatomic Rh contribute to this excellent catalytic performance by firstly facilitating oxygen vacancies formation to generate oxygen-vacancy-Rh Lewis-acid-base pairs, which favor CO 2 adsorption and activation, cleavage of CÀ O bonds in CH x OH* and COOH* into CH x * and CO* species, subsequent CÀ C coupling and hydrogenation into ethanol, and secondly generating strong RhÀ O bond by Ti-doping-induced crystal reconstruction, which contributes to striking stability. This work highlights the importance of support elaborating regulation for singleatom catalyst design to substantially improve the catalytic performance.

Development of Multifunctional Tandem Catalysts for CO2 Hydrogenation to Higher Alcohols

“…Rh has a weak C-C coupling ability, so it is necessary to introduce alkali metals or transition metals onto Rh-based catalysts to promote the formation of C2+ products [44,45]. Liu et al [46] embedded Rh into Ti-doped CeO2 carrier to construct a Rh1/CeTiOx single-atom catalyst, which exhibited high ethanol selectivity. The oxygen vacancy-Rh Lewis acid-base pairs are conducive to CO adsorption and activation.…”