催化学报

催化学报 ›› 2008, Vol. 29 ›› Issue (12): 1231-1236.

• 研究论文 • 上一篇    下一篇

担载型铱催化剂上CO吸附量热和红外光谱研究

王兴棠1,2,李林1,黄延强1,王晓东1,张涛1   

  1. 1 中国科学院大连化学物理研究所, 辽宁大连 116023; 2 中国科学院研究生院, 北京 100049
  • 收稿日期:2008-12-25 出版日期:2008-12-25 发布日期:2012-09-20

Microcalorimetric and FT-IR Studies of CO Adsorption on Supported Iridium Catalysts

WANG Xingtang1,2, LI Lin1, HUANG Yanqiang1, WANG Xiaodong1*, ZHANG Tao1*   

  1. 1 Dalian Institute of Chemical Physics, The Chinese Academy of Sciences, Dalian 116023, Liaoning, China; 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2008-12-25 Online:2008-12-25 Published:2012-09-20

PDF

990

被引次数

5

摘要： 分别对Al2O3和SiO2担载的不同含量铱(Ir)催化剂进行了H2程序升温还原、CO微量吸附量热和红外研究. 结果表明,还原后, Ir/Al2O3上存在金属态Ir0和氧化态Irδ+两种物种, CO在催化剂表面主要以线式和孪生吸附态存在,测量的CO吸附热为两种吸附形式的平均吸附热. 提高还原温度和Ir担载量, Ir/Al2O3表面CO线式吸附物种的比例增加,从而导致CO吸附热值的升高. 而在Ir/SiO2上Ir物种主要为金属态Ir0, CO吸附都以线式吸附为主,在所考察的条件下CO吸附热随Ir担载量和还原温度的变化不明显.

Abstract: For Ir/Al2O3, a pair of bands assigned to gem-dicarbonyl species adsorbed o n Irδ+ were overlapped with a carbonyl band due to linear species on Ir 0. The adsorption heat could be the average heat produced by the formation of both gem-dicarbonyl and linear species. For Ir/SiO2, several bands ranged in 2100-2000 cm-1 were identified and attributed to the linearly bonded CO to larger and smaller Ir0 clusters.