题名：Effect of Surface [Cu₄O] Moieties on the Activity of Cu-Based Catalysts

来源：ACS Catalysis

发表年代：2022年

作者：Yuan Fang, Hao Sun, Wei Peng, Qinghong Yuan,* and Chen Zhao*

Abstract: Cu-based catalysts have received extensive attention in thefield of catalysis due to their natural reserves, low cost, and superior catalyticperformance. However, the catalytic mechanism has been debated for decadesowing to the existence of various oxidation states of Cu and their dynamicalevolution during the reaction process. Herein, based on first-principlestheoretical calculations, a highly active [Cu₄O] moiety was identified on thepartially reduced Cu₂O(111) surface. In contrast to a previous mechanism inwhich Cu⁰, Cu⁺ , or their combination was proposed, Cu atoms in the [Cu4O]moiety are in a fractional oxidation state (+0.5) and have bondingcharacteristics analogous to both metallic Cu and Cu₂O. The [Cu₄O] moietyhas both electronic and geometric advantages in surface catalysis, showinghigh activity in methanol dehydrogenation. Experimental work furtherprovided evidence for the existence of such mixed-valence Cu species andconfirmed its high activity in methanol dehydrogenation. This work unravels the active sites in the partially reduced Cu species andprovides insights into the rational design of more active Cu-based catalysts.

Effect of Surface [Cu₄O] Moieties on the Activity of Cu-Based Catalysts.pdf