Short channeled Zr-Ce-SBA-15 supported palladium catalysts for toluene catalytic oxidation

摘要

Short channeled Zr-Ce-SBA-15 (ZCS) mesoporous materials were synthesized through hydrothermal routes without addition of mineral acids. 0.5 wt.% palladium was loaded on ZCS and SBA-15 via an ethanol reduction approach. Pd/ZCS possesses unique hexagonal platelet morphologies with short channels running parallel to the thickness in the range of 400-500 nm, while Pd/SBA-15 has a fibrous macrostructure with channels at the micrometer scale. Palladium species present in supports as well dispersed PdO nanocrystals with diameter of ca. 5-6 nm. Comparing with Pd/SBA-15, Pd/ZCS shows enhanced catalytic activity for toluene oxidation, which is ascribed to short channeled supports facilitating the molecular diffusion.