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Abstract：
Ba1-xCexMnO3 (BM-Cex) and Ba1-xLaxMn0.7Cu0.3O3 (BMC-Lax) perovskite-type mixed oxides were synthesized using the sol-gel method adapted for aqueous media with different values of x (0, 0.1, 0.3, 0.6) to estimate the effect of the degree of the partial substitution of Ba by Ce or La on the structure and properties that are relevant for their use as catalysts for gasoline direct injection (GDI) soot oxidation. The samples were deeply characterized by ICP-OES, XRD, XPS, N2 adsorption, H2-TPR, and O2-TPD, and their potential as catalysts for soot oxidation has been analyzed in various scenarios that replicate the exhaust conditions of a GDI engine. By comparing the catalytic performance for soot oxidation of the two tested series (BM-Cex and BMC-Lax) and in the two conditions used (100% He and 1% O2 in He), it could be concluded that (i) in the absence of oxygen in the reaction atmosphere (100% He), BMC-La0.1 is the best catalyst, as copper is also able to catalyze the soot oxidation; and (ii) if oxygen is present in the reaction atmosphere (1% O2/He), BM-Ce0.1 is the most-active catalyst as it presents a higher proportion of Mn(IV) than BMC-La0.1. Thus, it seems that the addition of an amount of Ce or La higher than that corresponding to x = 0.1 in Ba1-xCexMnO3 and Ba1-xLaxCu0.3Mn0.7O3 does not allow us to improve the catalytic performance of BM-Ce0.1 and BMC-La0.1 for soot oxidation in the tested conditions.
摘要：
使用溶胶-凝胶法合成了Ba1-xCexMnO3（BM-Cex）和Ba1-xLaxMn0.7Cu0.3O3（BMC-Lax）钙钛矿型混合氧化物，该氧化物适用于具有不同x值（0、0.1、0.3、0.6）的水性介质，以估计Ce或La部分取代Ba的程度对结构和性能的影响，这与它们用作汽油烟灰直接喷射的催化剂有关（GDI氧化通过ICP-OES对样品进行了深入表征，XRD,XPS,N2吸附，H2-TPR,和O2-TPD,以及它们作为烟灰氧化催化剂的潜力已经在复制GDI发动机排气条件的各种情况下进行了分析。通过比较两个测试系列（BM-Cex和BMC-Lax）以及在使用的两种条件（He中的100％He和1％O2）下的烟灰氧化催化性能，可以得出结论，（i）在反应气氛中不存在氧气（100％He）的情况下，BMC-La0.1是最好的催化剂，因为铜也能够催化烟灰氧化;和(ii)如果氧气存在于反应气氛中(1%O2/He),BM-Ce0.1是最具活性的催化剂，因为它比BMC-La0.1具有更高的Mn（IV）比例。因此，似乎在Ba1-xCexMnO3和Ba1-xLaxCu0.3Mn0.7O3中添加高于对应于x=0.1的Ce或La的量使我们无法改善BM-Ce0.1和BMC-La0.1在测试条件下对烟灰氧化的催化性能。
