Nested Metal Catalysts: Metal Atoms and Clusters Stabilized by Confinement with Accessibility on Supports

• Published in: Precision Chemistry Vol. 1; no. 1; pp. 3 - 13
• Main Authors: Gates, Bruce C., Katz, Alexander, Liu, Jingyue
• Format: Journal Article
• Language: English
• Published: United States University of Science and Technology of China and American Chemical Society 27.03.2023; American Chemical Society
• Subjects: atomically dispersed metal catalysts; catalyst synthesis; catalyst synthesis, supported metal catalysts, encapsulated catalysts, nested catalysts, atomically dispersed metal catalysts; catalysts; encapsulated catalysts; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; MATERIALS SCIENCE; metal clusters; metals; nested catalysts; platinum; supported metal catalysts; zeolites; encapsulated catalysts; atomically dispersed metal catalysts; supported metal catalysts; nested catalysts; catalyst synthesis
• ISSN: 2771-9316; 2771-9316
• DOI: 10.1021/prechem.2c00011

Supported catalysts that are important in technology prominently include atomically dispersed metals and metal clusters. When the metals are noble, they are typically unstablesusceptible to sinteringespecially under reducing conditions. Embedding the metals in supports such as organic polymers, metal oxides, and zeolites confers stability on the metals but at the cost of catalytic activity associated with the lack of accessibility of metal bonding sites to reactants. An approach to stabilizing noble metal catalysts while maintaining their accessibility involves anchoring them in molecular-scale nests that are in or on supports. The nests include zeolite pore mouths, zeolite surface cups (half-cages), raft-like islands of oxophilic metals bonded to metal oxide supports, clusters of non-noble metals (e.g., hosting noble metals as single-atom alloys), and nanoscale metal oxide islands that selectively bond to the catalytic metals, isolating them from the support. These examples illustrate a trend toward precision in the synthesis of solid catalysts, and the latter two classes of nested catalysts offer realistic prospects for economical large-scale application.