Highly active MnOx-CeO2 catalyst for diesel soot combustion
Highly active MnOx-CeO2 catalyst for diesel soot combustion
复制标题
用于柴油机烟灰燃烧的高活性 MnOx-CeO2 催化剂
DOI：
10.1039/c6ra25738k
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发表时间：
2017
期刊：
影响因子：
3.9
通讯作者：
Shi Jianlin
中科院分区：
文献类型：
--
作者：
Zhao Han;Zhou Xiaoxia;Wang Min;Xie Zhiguo;Chen Hangrong;Shi Jianlin
采用易共沉淀法制备了一系列MnOx-CeO2复合材料，并将其用作柴油烟尘燃烧催化剂。研究发现，在NOx和O2共同存在的情况下，氧化锰的含量对柴油烟尘燃烧的形态和催化活性都有相当大的影响。优化后的催化剂CM20 [Mn/(Mn + Ce) = 20 at%]具有优异的催化活性（Tf = 360°C），其原因可以归结为以下两个方面：(1)与煤烟颗粒大小相近的松散均匀颗粒之间存在丰富的孔隙结构，有利于传质和热扩散，催化剂与煤烟之间有充分的接触；(2) Mn和Ce之间的电荷转移产生高浓度的Mn4+和Ce3+阳离子作为活性位点，可以吸附和激活NO和O2，从而大大促进NO2的生成。
A series of MnOx–CeO2 composites have been prepared via a facile coprecipitation method and used as catalysts for diesel soot combustion. It is found that the content of manganese oxide has a considerable influence on both the morphology and catalytic activity for diesel soot combustion in the copresence of NOx and O2. Superior catalytic activity (Tf = 360 °C) was obtained over the optimized catalyst CM20 [Mn/(Mn + Ce) equals to 20 at%], which is believed to be attributable to the following two aspects: (1) the abundant pore structure, presenting between the loosely-packed homogeneous particles with similar sizes to that of the soot particles, which is beneficial for mass transfer and heat diffusion as well as the sufficient contact between catalyst and soot; (2) high concentration of Mn4+ and Ce3+ cations derived from the charge transfer between Mn and Ce species as active sites can adsorb and activate NO and O2, and then greatly facilitate NO2 production.