Heterostructure-strengthened metal-support interaction of single-atom Pd catalysts enabling efficient oxygen activation for CO and VOC oxidation

Abstract

Catalytic oxidation of air pollutants depends on the active oxygen species, which requires a deep understanding of the active sites responsible for oxygen activation. In this study, we utilized a heterostructured support (ZnMn2O4@MnO2) to modulate the metal-support interactions (MSIs) in single-atom Pd catalysts, achieving efficient activation of both adsorbed oxygen (Oads) and lattice oxygen (Olatt). Specifically, the tailored MSIs induced an efficient redox pair for CO oxidation, i.e., Pd1O3 and Pd1O5, promoting the activation of O2 to Oads, which led to 90% CO conversion at room temperature and a novel “MvK-induced L-H” reaction mechanism. Moreover, the tailored MSIs induced the stretching of the Mn-O bond, facilitating the participation of Olatt in toluene oxidation. Our results demonstrate a novel approach to modulating MSIs in single-atom catalysts (SACs) and highlight the superiority of the strong MSIs introduced by heterostructured supports for oxygen activation.