【摘 要】
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Au-Cu bimetallic nanoparticles with uniform size,shape,and compositions were synthesized by wet chemistry method,and then the Au-Cu/SiO2 catalyst sup-ported on
【机 构】
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Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis,School of Chemi
论文部分内容阅读
Au-Cu bimetallic nanoparticles with uniform size,shape,and compositions were synthesized by wet chemistry method,and then the Au-Cu/SiO2 catalyst sup-ported on SiO2 was prepared.Meanwhile,their catalytic activity for the selective oxidation of propene to acrolein using O2 as an oxidant was evaluated.The bimetallic cat-alyst shows a significantly enhanced catalytic performance comparing with Au and Cu monometallic catalysts.Char-acterization of the materials and kinetic study was con-ducted to explore the cooperating mechanism of Au and Cu for improving the catalytic activity of the bimetallic cata-lyst.Cu component can segregate to the alloy surface and the Au-Cu alloy transferred to Au-CuO core/shell struc-ture after annealing during the preparation process.Based on the Mars-van Krevelen mechanism for the selective oxidation of propene over the prepared catalysts,the coexistence of CuO can promote the adsorption and acti-vation of O2.Meanwhile,the electrons transfer from Au to Cu in the catalyst can facilitate the adsorptions of both oxygen on CuO sites and propene on Au sites.The com-bined effects of the above two aspects result in the high catalytic activity of the Au-Cu/SiO2 catalyst for selective oxidation of propene to acrolein,compared to the Au/SiO2 and CuO/SiO2 catalysts.
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