Al-modified Mesoporous SiO2-matrix-supported Uniform CeO2 Nanodots with Superior Catalytic Efficiency in DCE Combustion

摘要

Adjusting the acidity and/or oxygen species on the surface of metal oxide nanostructures could fabricate the high active and durable catalysts for the combustion of chlorinated volatile organic compounds (CVOCs). Herein, Al-modified mesoporous SiO2 matrix supported uniform CeO2 nanodots (CeO2@xAlSiO(2)) was synthesized and evaluated in dichloroethane (DCE) catalytic combustion. From the systematic study of the texture structure, surface properties, and catalytic activity, we deduced that the improved surface acidity and oxygen species activity enhanced the DCE conversion and reduced the formation of chlorinated organic byproduct, while increasing the formation of the desired product, HCl. The optimized CeO2@0.5AlSiO(2) sample showed superior activity (90 conversion of DCE at 260 degrees C), excellent durability (at 280 degrees C for 60 h) and good tolerance towards moisture (in 1 and 3 moisture for 10 h, respectively). Our work identified the important role of surface acidity and oxygen species over these functionalized catalysts, providing guidance for the advanced catalyst design.