Ga-doped Pd/CeO2 model catalysts for CO oxidation reactivity: A density functional theory study

Ceria-supported Pd single-atom catalysts (SACs) are important catalysts to catalyze the CO oxidation, often used in three-way catalysts to treat automobile exhaust gases. This paper uses density functional theory (DFT) calculations and transition state theory to systematically study the effect of Ga atom doping on the performance of the Pd/CeO2 SACs system. Noticeably, the results of DFT calculations reveal that the stability of Pd single atoms supported on the surface of CeO2(111) was significantly augmented by doping Ga. An oxygen vacancy generated easily near the Ga and Pd site will act as a crucial role for activating the adsorbed oxygen molecule. Most importantly, the climbing image nudged elastic band (CINEB) calculations show that the doping of Ga remarkably reduces the highest energy barrier during the CO oxidation reaction, meaning that the catalytic performance of the CO oxidation reaction is promoted effectively. This work provides a new perspective for SACs modification.

Automated summary

This study systematically investigated the effect of Ga doping on the performance of Pd/CeO2 SACs system using DFT calculations and transition state theory. Ga doping significantly enhanced the stability of Pd single atoms and promoted the catalytic performance of the CO oxidation reaction effectively. This work provides a new perspective for SACs modification.