Electronic interactions between neighboring functionalized guest Sb single atoms and Pt clusters enhance CO tolerance

Platinum-based (Pt) catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide (CO) poisoning. Overcoming this poisoning deactivation of Pt-based catalysts while enhancing their catalytic activity, selectivity, and durability remains a major challenge. Herein, we propose a strategy to enhance the CO tolerance of Pt clusters (Pt_n) by introducing neighboring functionalized guest single atoms (such as Fe, Co, Ni, Cu, Sb, and Bi). Among them, antimony (Sb) single atoms (SAs) exhibit significant performance enhancement, achieving 99% CO selectivity and 33.6% CO₂ conversion at 450 °C. Experimental results and density functional theory (DFT) calculations indicate the optimization arises from the electronic interaction between neighboring functionalized Sb SAs and Pt clusters, leading to optimal 5d electron redistribution in Pt clusters compared to other functionalized guest single atoms. The redistribution of 5d electrons weaken both the σ donation and π backdonation interactions, resulting in a weakened bond strength with CO and enhancing catalyst activity and selectivity. In situ environmental transmission electron microscopy (ETEM) further demonstrates the exception thermal stability of the catalyst, even under H₂ at 700 °C. Notably, the functionalized Sb SAs also improve CO tolerance in various heterogenous catalysts, including Co/CeO₂, Ni/CeO₂, Pt/Al₂O₃, and Pt/CeO₂-C. This finding provides an effective approach to overcome the primary challenge of CO poisoning in Pt-based catalysts, making their broader applications in various industrial catalysts.