Etching-Induced Pt_3<i>x</i>Cu_<i>y</i> Atom Clusters Encapsulated in Silicate-1 Promote H₂O Dissociation for the Water–Gas Shift Reaction

Alloy nanocatalysts prevail in both thermal and electrochemical reactions due to the enhanced catalytic performance through modifications to the structural and electronic properties by alloying with other metal elements. This synergetic effect, achieved by combining two or more metal elements in a geometrically confined space, remains largely unexplored. Herein, we synthesize PtCu atom clusters encapsulated within a Silicate-1 zeolite framework and tune their compositions through a controlled etching process. The synergistic balance between CO adsorption on Pt sites and H2O dissociation on Cu sites significantly enhances the catalytic performance in the water–gas shift reaction. Additionally, the modified microenvironment of the Si–O framework postetching plays a pivotal role in constructing stable ensembles for efficient CO conversion. This strategy can be extended to the creation of multielement single-cluster catalysts within confined spaces, tailored for specific catalytic processes.