Key Laboratory of Functional Inorganic Material Chemistry (Heilongjiang University), Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, 150080 P. R. China.
Sci Rep. 2016 Jun 29;6:29062. doi: 10.1038/srep29062.
In this study, nano-structure ceria with three different morphologies (nanorod, nanoparticle and flake) have been prepared by hydrothermal and solvothermal methods. The ceria samples were deeply characterized by XRD, SEM, TEM, H2-TPR, XPS and in-situ DRIFTS, and tested for soot combustion in absence/presence NO atmospheres under loose and tight contact conditions. The prepared ceria samples exhibit excellent catalytic activities, especially, the CeO2 with nanorod (Ce-R) shows the best catalytic activity, for which the peak temperature of soot combustion (Tm) is about 500 and 368 °C in loose and tight contact conditions, respectively. The catalytic activity for Ce-R is higher than that of the reported CeO2 catalysts and reaches a level that of precious metals. The characterization results reveal that the maximal amounts of adsorbed oxygen species on the surface of the nanostructure Ce-R catalyst should be the crucial role to decide the catalytic soot performance. High BET surface area may also be a positive effect on soot oxidation activity under loose contact conditions.
在这项研究中，采用水热法和溶剂热法制备了具有三种不同形态（纳米棒、纳米颗粒和薄片）的纳米结构氧化铈。通过 XRD、SEM、TEM、H2-TPR、XPS 和原位 DRIFTS 对氧化铈样品进行了深入表征，并在松散和紧密接触条件下在不存在/存在 NO 气氛下测试了其对炭黑燃烧的催化性能。所制备的氧化铈样品表现出优异的催化活性，特别是具有纳米棒形貌的氧化铈（Ce-R）表现出最好的催化活性，其在松散和紧密接触条件下的炭黑燃烧峰温（Tm）分别约为 500°C 和 368°C。Ce-R 的催化活性高于已报道的 CeO2 催化剂，达到了贵金属的水平。表征结果表明，纳米结构 Ce-R 催化剂表面吸附氧物种的最大量应该是决定催化炭黑性能的关键因素。高 BET 比表面积也可能对松散接触条件下的炭黑氧化活性有积极影响。
