Ir/CeO_2催化剂的表征和CO氧化性能  

Ir/CeO_2 Catalysts:Characterization and Performance for CO Oxidation

作　　者：胡盼静[1] 伍燕妮[1] 郑海影[1] 孟涟[1] 金凌云[1] 罗孟飞[1] 

机构地区：[1]浙江师范大学物理化学研究所,浙江省固体表面反应化学重点实验室,金华321004

出　　处：《无机化学学报》2011年第12期2389-2394,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.20873125)资助项目

摘　　要：采用浸渍法制备了Ir/CeO2催化剂,考察了催化剂的CO氧化活性。随着Ir负载量的增加,Ir/CeO2催化剂的CO氧化活性先上升后下降,当Ir的负载量为1%时,催化剂的活性最高。Ir/CeO2催化剂中Ir以IrO2的形式存在,当低负载量(≤1%)时以高分散形式存在;高负载量(>1%)时以晶相IrO2的形式存在。随着Ir负载量增加,Ir粒子逐渐变大,反应比速率和反应转换频率(TOF)逐渐下降,表明小粒子上具有更高的CO反应活性。同时也发现金属态Ir催化剂的CO氧化活性高于氧化态IrOx催化剂。A series of Ir/CeO2 catalysts were prepared by an impregnation method,and were tested for CO oxidation.It was found that the activity of Ir/CeO2 catalysts for CO catalytic oxidation rose first and then declined with Ir loading.The catalysts showed the highest activity when Ir content was 1%.Ir existed in the form of IrO2 in the Ir/CeO2 catalysts.IrO2 was highly dispersed with low Ir loading（≤1%）,and existed as crystalline phase with high Ir loading（1%）.Ir particle size increased gradually with Ir loading,but specific rate and turnover frequency（TOF） declined gradually.It indicated that the catalyst with small particle size had a higher CO reactivity.It was also found that for CO oxidation,the activity of Ir catalyst with metal state was higher than that with oxidation state.

关 键 词：Ir/CeO2催化剂 CO氧化 转换频率(TOF) 

分 类 号：O643.3[理学—物理化学]