H 2 O-Enabled Switch of the CO Oxidation Pathway on Zeolite-Confined Cationic Pd Catalysts

作者：Wuwan Xiong, Hairong Cheng, Alberto Lopez, Huarong Lei, Fei Li, Paolo Centomo, Carlo Meneghini, Leneng Yang, Daiqi Ye, Ulrich Simon, Abhishek Khetan, Peirong Chen · 发表于：ACS Catalysis · 年份：2025 · DOI：10.1021/acscatal.5c04639 · 被引用次数：2 · 研究领域：Catalytic Processes in Materials Science、Catalysis and Oxidation Reactions、Ammonia Synthesis and Nitrogen Reduction

Understanding reaction-driven dynamics of Pd sites is crucial for rationalizing the design of high-performance Pd-zeolites for environmental and energy catalysis. Using Pd-SSZ-13 zeolite as catalyst, we demonstrate that H2O, an unavoidable component in reality, promoted CO oxidation by facilitating O2 activation on Pd sites. In situ spectroscopic interrogations and QM/MM simulations revealed that the cationic Pd sites, initially coordinated firmly on the zeolite framework, were solvated upon interaction with H2O, forming partially detached Pd–H2O complexes that favored the reaction of CO and O2 via the Langmuir–Hinshelwood mechanism. By contrast, CO on bare Pd site reacts with O2 in the gas phase via the thermodynamically less favorable Eley–Rideal mechanism.