Enhanced catalytic performance for selective oxidation of propene with O2 over bimetallic Au-Cu/SiO2 catalysts

• 作者: Xin Guo Xue-Quan Sun Yun Guo Yang-Long Guo Yun-Song Wang Li Wang Wang-Cheng Zhan
• 来源期刊: 稀有金属（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 1056-1066
• 页数: 11页
• 语种: 英文

摘要

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.