催化学报

催化学报 ›› 2006, Vol. 27 ›› Issue (5): 381-385.

• 研究论文 • 上一篇    下一篇

利用多孔阳极氧化铝研究载体孔洞尺寸对负载银粒子团聚的影响

赵红1,2,姜志全1,张镇1,翟润生1,包信和1   

  1. 1 中国科学院大连化学物理研究所催化基础国家重点实验室, 辽宁大连 116023; 2 大连交通大学环境科学与工程学院, 辽宁大连 116028
  • 收稿日期:2006-05-25 出版日期:2006-05-25 发布日期:2006-05-25

Study of Support Pore Size Dependence of Silver Particle Agglomeration by Applying Ordered Porous Anodic Alumina

ZHAO Hong1,2, JIANG Zhiquan1, ZHANG Zhen1, ZHAI Runsheng1, BAO Xinhe1*   

  1. 1 State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023, Liaoning, China; 2 School of Environmental Science and Engineering, Dalian Jiaotong University, Dalian 116028, Liaoning, China
  • Received:2006-05-25 Online:2006-05-25 Published:2006-05-25

PDF

972

被引次数

16

摘要： 利用阳极氧化方法制备了具有规整的可控孔洞尺寸的多孔Al2O3 膜,并以此模拟实际的催化剂载体制备了负载银催化剂. 采用扫描电镜、能量分散谱、透射电镜、X射线衍射和X射线光电子能谱等手段,研究了多孔阳极氧化铝的孔洞大小对负载的银粒子团聚的影响. 结果表明,载体孔洞尺寸对银粒子团聚可能起到限制作用,而且这种限制作用随载体孔洞尺寸增大而减小. 当载体的孔洞尺寸约为50 nm时,随温度升高银粒子的团聚和生长都不明显; 当载体的孔洞尺寸约为200 nm时,随温度升高银粒子发生一定程度的团聚和生长,但孔洞尺寸的限制作用仍存在. 这种载体尺寸的限制作用可以有效地阻止催化剂活性组分的团聚.

关键词: 阳极氧化铝, 银, 团聚, 乙烯, 环氧化

Abstract: Ordered porous alumina films with a controllable pore size were fabricated by anodization and applied to simulate realistic catalyst supports. The support morphology dependence of the silver particle agglomeration on the Ag model catalyst loaded on this ordered porous anodic alumina was studied. Scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscope, X-ray diffraction and X-ray photoelectron spectroscopy were used to characterize the morphologies, compositions, and chemical properties of the model catalyst. When the average pore size of the alumina substrate is smaller than 50 nm, both the agglomeration and the growth of silver particles are suppressed greatly. But when the pore size is bigger than 200 nm, the agglomeration and growth of silver particles occur to some extent, while the confinement effect still exists. This confinement effect can efficiently prevent active components on catalysts from aggregation.

Key words: porous anodic alumina, silver, agglomeration, ethylene, epoxidation