Single-Site vs. Cluster Catalysis in High Temperature Oxidations

被引：38

作者：

Serna, Pedro ^{[1
]}

Rodriguez-Fernandez, Aida ^{[2
]}

Yacob, Sara ^{[1
]}

Kliewer, Christine ^{[1
]}

Moliner, Manuel ^{[2
]}

Corma, Avelino ^{[2
]}

机构：

[1] ExxonMobil Res & Engn Co, Corp Strateg Res, Annandale, NJ 08801 USA

[2] Univ Politecn Valencia, Consejo Super Invest Cient UPV CSIC, Inst Tecnol Quim, Ave Naranjos S-N, Valencia 46022, Spain

来源：

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION | 2021年 / 60卷 / 29期

关键词：

metal clusters; oxidation catalysts; single sites; structure-activity relationship; zeolites; X-RAY-ABSORPTION; METAL-CATALYSTS; CO OXIDATION; HETEROGENEOUS CATALYSIS; SUPPORTED RHODIUM; PLATINUM; ZEOLITE; METHANE; CHABAZITE; OXYGEN;

D O I：

10.1002/anie.202102339

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The behavior of single Pt atoms and small Pt clusters was investigated for high-temperature oxidations. The high stability of these molecular sites in CHA is a key to intrinsic structure-performance descriptions of elemental steps such as O-2 dissociation, and subsequent oxidation catalysis. Subtle changes in the atomic structure of Pt are responsible for drastic changes in performance driven by specific gas/metal/support interactions. Whereas single Pt atoms and Pt clusters (> ca. 1 nm) are unable to activate, scramble, and desorb two O-2 molecules at moderate T (200 degrees C), clusters <1 nm do so catalytically, but undergo oxidative fragmentation. Oxidation of alkanes at high T is attributed to stable single Pt atoms, and the C-H cleavage is inferred to be rate-determining and less sensitive to changes in metal nuclearity compared to its effect on O-2 scrambling. In contrast, when combustion involves CO, catalysis is dominated by metal clusters, not single Pt atoms.

引用

页码：15954 / 15962

页数：9