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Title: Pt 1 –O 4 as active sites boosting CO oxidation via a non-classical Mars–van Krevelen mechanism
Single-atom catalysts (SACs) exhibit excellent performance for various catalytic reactions but it is still challenging to have adequate total activity for practical applications. Here we report the high-valence, square planar Pt 1 –O 4 as an active site that enables significantly to increase the total activity of the Pt 1 /Fe 2 O 3 SAC with a Pt loading of only ∼30 ppm, which is similar to that of a 1.0 wt% nano-Pt/Fe 2 O 3 , for CO oxidation at 350 °C. Density functional theory calculations reveal that Pt 1 –O 4 catalyzes CO oxidation through a non-classical Mars–van Krevelen mechanism. The adsorbed O 2 on Pt 1 atoms activates the coordination oxygen in the Pt 1 –O 4 configuration, and then a barrierless O 2 dissociation occurs on the Pt 1 –Fe 2 triangle to replenish the consumed coordination oxygen by the cooperative action of Pt 5d and Fe 3d electrons. This work provides a new fundamental understanding of oxidation catalysis on stable and active SACs, providing guidance for rationally designing future heterogeneous catalysts.  more » « less
Award ID(s):
1955474
PAR ID:
10293354
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
11
Issue:
10
ISSN:
2044-4753
Page Range / eLocation ID:
3578 to 3588
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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