【摘要】 采用柠檬酸络合燃烧法制备了一系列铝铈复合氧化物(铝掺杂的氧化铈),并通过程序升温氧化反应在紧密接触的模式下研究了其催化氧化碳烟的活性.结果表明,氧化铝和氧化铈之间存在强烈的相互作用,部分铝可以进入氧化铈晶格形成铝铈固溶体,大部分铝以γ-Αl2O3形式存在.与纯氧化铈相比,铝铈复合氧化物具有较好的催化燃烧活性,这是由于γ-Αl2O3能作为"扩散阻碍"阻止氧化铈粒子之间的接触而增强其热稳定.晶格氧的活动性决定了铝铈复合氧化物的催化活性,当铝与铈的摩尔比为1:30时,复合氧化物的催化活性最高.更多还原

【Abstract】 A series of Al-doped CeO2 catalysts (n-AlCeO2, where n represents the molar ratio of Ce to Al in the samples) were prepared by a citric acid complexation-combustion method and used for soot combustion. There is a strong interaction between CeO2 and Al2O3 in the mixed oxide, and some aluminum can be incorporated into the CeO2 lattice forming a solid solution. The existence of γ-Al2O3 in the mixed oxide obviously improved the thermal stability of CeO2 as a "diffusion barrier", which induced a higher catalytic activity of the mixed oxides compared with the pure CeO2. For the Al-containing samples, the mobility of surface lattice oxygen seems to play an important role in soot combustion. The 30-AlCeO2 sample exhibited the highest soot combustion activity with the temperature corresponding to the CO2 + CO peak of 356 oC.更多还原