摘要
以Na2 CO3 ·1 0H2 O和NaOH混合碱为沉淀剂 ,采用共沉淀法制备了钙钛矿型结构的La1 x yBaxREyMnO3 (RE =Dy或Y)复合氧化物超细粒子 .该复合氧化物超细粒子具有较大的比表面积和良好的热稳定性 (经 70 0和 1 0 0 0℃焙烧后 ,其比表面积仍分别可达到 4 7 0和 1 6 9m2 /g) .随着LaMnO3 中的La3 + 被Ba2 + 及稀土离子Dy3 + 或Y3 + 部分取代后 。
Perovskite type oxide (ABO 3) is one of the most promising catalysts for combustion of carbon monoxide and methane. However, owing to their small specific surface area and poor textural thermostability, the conversion on unit mass of ABO 3 is not high. La 1 x y Ba x RE y MnO 3 (RE=Dy or Y) composite oxides with perovskite structure were prepared by co precipitation method with Na 2CO 3·10H 2O NaOH as a precipitant. The composite oxides were characterized by XRD, BET and XPS, and their catalytic activity in methane combustion was investigated. The relationship of their thermostability and catalytic activity with their surface structure was analyzed. The as prepared oxides exhibited higher surface area and better thermostability than LaMnO 3, and their surface area was close to 47 0 and 16 9 m 2/g after calcination at 700 and 1?000 ℃, respectively. When La 3+ in LaMnO 3 was partially substituted by Ba 2+ and Dy 3+ or Y 3+ , their thermostability was improved effectively, and they exhibited higher activity in methane combustion.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2004年第7期577-580,共4页
基金
国家自然科学基金资助项目 ( 2 0 2 63 0 0 2 )
关键词
镧
锰
钡
镝
钇
复合氧化物
超细粒子
甲烷
催化燃烧
lanthanum, manganese, barium, dysprosium, yttrium, composite oxide, ultrafine particle, methane, catalytic combustion
