Zhai Guangjun, Wang Jinguo, Chen Zimei, Yang Shuaifeng, Men Yong
College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, PR China.
College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, PR China.
J Hazard Mater. 2019 Feb 5;363:214-226. doi: 10.1016/j.jhazmat.2018.08.065. Epub 2018 Sep 24.
Three-dimensionally ordered macroporous (3DOM) CoO-CeO catalysts with controllable Co/Ce molar ratios synthesized by colloidal crystal template method were developed to catalyze the NO-assisted soot oxidation for the first time, and the obtained 3DOM CoO-CeO catalysts exhibited highly enhanced soot oxidation activity. Detailed characterizations of 3DOM CoO-CeO catalysts revealed that the highly enhanced soot oxidation activity was originated from the synergistic promoting effect by combining the macroporous effect resulted from the unique 3DOM framework, the chemical nature associated with more Co reactive sites, the surface enrichment of Ce species and the improved redox properties. Meanwhile, the high NO storage and oxidation capacity resulted from the integrated respective merits of CoO and CeO also accounted for the enhanced soot oxidation activity via NO-assisted mechanism. Furthermore, the 3DOM CoO-CeO catalysts demonstrated strong stability because of the surface enrichment of Ce species improving the thermal stability and the robust 3DOM framework inhibiting the structural collapse, showing their potential applications under practical conditions.
首次开发了通过胶体晶体模板法合成的具有可控Co/Ce摩尔比的三维有序大孔（3DOM）CoO-CeO催化剂，用于催化NO辅助的碳烟氧化，所制备的3DOM CoO-CeO催化剂表现出高度增强的碳烟氧化活性。对3DOM CoO-CeO催化剂的详细表征表明，高度增强的碳烟氧化活性源于独特的3DOM结构产生的大孔效应、更多Co活性位点相关的化学性质、Ce物种的表面富集以及改善的氧化还原性能的协同促进作用。同时，CoO和CeO各自优点的结合所导致的高NO储存和氧化能力也通过NO辅助机制解释了增强的碳烟氧化活性。此外，由于Ce物种的表面富集提高了热稳定性以及坚固的3DOM结构抑制了结构坍塌，3DOM CoO-CeO催化剂表现出很强的稳定性，显示了它们在实际条件下的潜在应用。
