摘要
用共沉淀法制备了LaFeO3 ,LaFe0 96Pd0 0 4 O3 ,LaCoO3 ,LaCo0 96Pd0 0 4 O3 四种催化剂 ,用X 射线衍射仪 (XRD)对催化剂进行了结构分析 .程序升温还原 (TPR)实验揭示催化剂中存在两种类型的氧种 :α氧和β氧 .活性评价和TPR实验表明 ,α氧是CO和C3 H6氧化反应的活性氧种 ,而C3 H8的氧化则由α氧和β氧共同来完成 .Pd的掺杂可使ABO3 中 β氧的活性增强 ,从而使三效活性得以明显提高 .
Perovskite-type catalysts,LaFeO 3,LaFe 0.96 Pd 0.04 O 3,LaCoO 3 and LaCo 0.96 Pd 0.04 O 3 were prepared by co-preciptitation method.Catalyst structures have been characterized by means of X-ray diffraction(XRD).Two oxygen species,α and β,have been found in temperature programmed reduction(TPR)experiments.Activity tests and TPR experiments indicated that oxidation activities of CO and C 3H 6 were related with α oxygen while oxidation activites of C 3H 8 were determined by both α and β oxygen.Palladium introduced in the structure of ABO 3 could promote the activity of β oxygen,then the three-way catalytic performance could be promoted remarkably.
出处
《环境化学》
CAS
CSCD
北大核心
2002年第3期218-223,共6页
Environmental Chemistry
