Silicalite-1-Confined Synergistic Effects of Bimetallic Oxide Nanoclusters toward High Water Resistance for Complete Propane Oxidation.

Water-induced deactivation of Pd-based catalysts for light alkane combustion remains a significant challenge. Herein, S-1 zeolite-encapsulated Pd-Pt bimetallic oxide nanoclusters were prepared for catalytic propane oxidation. The optimized Pd0.8Pt0.2@S-1 catalyst exhibits exceptional water resistance with the propane oxidation reaction temperature (T90) shifting by a mere 9 °C in the presence of 5% H2O and fully recovering once the water feed is terminated, superior activity, and thermal stability. Combined experimental and theoretical insights reveal that the introduction of Pt induces the formation of Pt-O-Pd bonds, modulating the electronic structure of Pd to enhance surface hydrophobicity, optimize oxygen and propane adsorption, and promote propane activation. In situ DRIFTS studies further confirm that propane oxidation over Pd0.8Pt0.2@S-1 proceeds via a Mars-van Krevelen mechanism. This work sheds new light on confined bimetallic synergistic effects for the rational design of catalysts with superior performance.