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分别在以P123为软模板和无P123的条件下制备8个钙钛矿型催化剂La_(1-x)Sr_xCo_(1-y)Cu_yO_3(x=0,0.1;y=0,0.2),用X射线衍射(XRD)、扫描电镜(SEM)、X射线能谱仪(EDS)、BET和X射线光电子能谱(XPS)进行了表征,并测试了它们对CO+NO反应的催化活性。结果表明,以P123为软模板制备的催化剂具有更多大孔径段的介孔和小孔径段的大孔,更大的孔容,更多的氧空位,同时表面La的偏析更少,表面Co的含量以及Co~(3+)/Co~(2+)比例更高。因而,催化剂的催化活性明显优于无模板法制备的催化剂,其中对NO转化率的提升尤为显著。Sr对La的适量取代可以促进CO的氧化反应,而Cu掺杂会降低CO和NO的转化率。
Eight perovskite catalysts La_ (1-x) Sr_xCo_ (1-y) Cu_yO_3 (x = 0,0.1; y = 0,0.2) were prepared under the conditions of P123 as soft template and without P123. X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (EDS), BET and X-ray photoelectron spectroscopy (XPS) were used to characterize their catalytic activities. The results show that the catalyst prepared with P123 as a soft template has more mesopores and smaller pore size macropores, larger pore volume, more oxygen vacancies, and less surface segregation of La. The surface Co The content of Co ~ (3 +) / Co ~ (2+) is higher. Therefore, the catalytic activity of the catalyst is obviously superior to that of the catalyst prepared without the template method, and the improvement of the NO conversion rate is particularly remarkable. The appropriate substitution of Sr for La promoted the oxidation of CO, while Cu doping reduced the conversion of CO and NO.