In Situ Sulfide-Induced Surface Reconstruction of Catalysts for Enhanced Hydrogenation Efficiency and Sulfur Resistance

The development of sulfur-resistant nonhomogeneous noble metal catalysts with high activity and stability remains a significant challenge. In this work, Pd4S/ZSM-5 catalysts were prepared via in situ sulfidation-induced catalyst surface reconstruction and their sulfur-resistant performance in the hydrogenation of sulfur-containing substrates was systematically evaluated. Structural analysis revealed that Pd/ZSM-5 and Pd4S/ZSM-5 catalysts had similar morphologies and physicochemical properties. However, they differed notably in hydrogenation activity (Pd > Pd4S) and sulfur resistance (Pd < Pd4S). Overall, Pd4S/ZSM-5 has the best stability for catalytic hydrogenation of sulfur-containing substrates in sulfur-containing systems, and its turnover frequency (1471 h–1) is about 5 times higher than that of PdxSy/C (281.09 h–1) during the hydrogenation of 4-nitrothioanisole. Furthermore, Pd4S/ZSM-5 retained its activity across at least 10 reactions without significant deactivation. System characterization and density functional theory calculations suggest that the enhanced sulfur resistance of Pd4S/ZSM-5 is due to the reduced adsorption strength and energy of the sulfur-containing molecules, along with the improved selectivity for –NO2. This study provides valuable insights for designing and optimizing sulfur-resistant noble metal catalysts.