In situ study of ceria trapping Pt cluster under heating condition and the resulted strong metal‒support interaction effect in CO oxidation

The synergistic relationship between platinum (Pt) and ceria support is vital for advancing the innovative design of Pt/ceria catalyst, which extensively applied in the fields of energy conversion and environmental remediation. Through thermal treatment, A serial of Pt/ceria with different metal support interaction were obtained. Advanced analyses employing in situ transmission electron microscopy (TEM) and X-ray Photon-electron Spectroscopy (XPS) elucidated that these thermal methods provoke a marked affinity between the Pt clusters and ceria support. High-temperature treatment can result in partial encapsulation of Pt clusters by CeO2, enabling the Pt clusters to match to the CeO2 lattice. Notably, high-temperature treatments lead to the partial encapsulation of Pt clusters by CeO2, facilitating alignment of the Pt clusters with the CeO2 lattice. This results in the emergence of oxidized Pt (Pt4+), which replaces the initial metallic Pt0, embedding itself onto the ceria support and subsequently activating adjacent Ce atoms in proximity to Pt. This innovative structure creates more site for CO adsorption but with weaker adsorption energy, effectively eliminating CO poisoning on the Pt surface and enhancing O2 dissociative adsorption. Collectively, these modifications birth a catalyst exhibiting remarkable proficiency in low-temperature CO oxidation.