Local environmental engineering for highly stable single-atom Pt₁/CeO₂catalysts: first-principles insights

Single-atom Pt₁/CeO₂catalysts may cope with the high cost and durability issues of fuel cell electrocatalysts. In the present study, the stability and underlying interaction mechanisms of the Pt₁/CeO₂system are systematically investigated using first-principles calculations. The Pt adsorption energy on CeO₂surfaces can be divided into chemical interaction and surface deformation parts. The interaction energy, mainly associated with the local chemical environment, i.e. the number of Pt-O bonds, plays a major role in Pt₁/CeO₂stability. When forming a Pt-4O configuration, the catalytic system has the highest stability and Pt is oxidized to Pt²⁺. An electronic metal-support interaction mechanism is proposed for understanding Pt₁/CeO₂stability. In addition, our calculations show that the Pt₁/CeO₂(100) system is dynamically stable, and the external O environment can promote the further oxidation of Pt to Ptⁿ⁺(2 ≤n< 4). The present study provides useful guidance for the experimental development of highly stable and efficient electrocatalysts for fuel cell applications.