Fractional-hydrolysis-driven formation of nonuniform dopant concentration catalyst nanoparticles of Cr/CexZr1-xO2 and their catalysis in oxidation of NO
Fractional-hydrolysis-driven formation of nonuniform dopant concentration catalyst nanoparticles of Cr/CexZr1-xO2 and their catalysis in oxidation of NO
复制标题
分级水解驱动的Cr/CexZr1-xO2不均匀掺杂浓度催化剂纳米颗粒的形成及其对NO氧化的催化作用
DOI：
10.1016/j.cej.2013.09.032
复制
发表时间：
2014-01-15
影响因子：
15.1
通讯作者：
Zhao, Wei
中科院分区：
文献类型：
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作者：
Cai, Wei;Zhong, Qin;Zhao, Wei
采用一种简单、低成本的方法制备了Cr/CeO 2固溶体（Cr/CexZr 1-xO 2）纳米颗粒作为NO氧化催化剂。本发明利用水相反应，简化了实验步骤，节约了成本，并使Ce在产物表面富集。浸渍法使Cr在产物表面富集，提高了掺杂效率。采用XRD、拉曼、BET、TEM、XPS、NO（或O-2）-TPD和UV-vis等技术对产物的理化性质进行了研究。结果表明，富锆样品具有四方晶系结构，比表面积增大，粒径减小，对NO和O2-的吸附容量高于富铈样品。因此，Cr/Ce0.14Zr0.86O2催化剂具有较高的NO氧化活性，在300 ℃时达到62.18%。UV-vis分析表明，吸附态NO与吸附态O-2的相互作用符合L-H模型。动力学试验证实了上述结论。(C)2013 Elsevier B. V.保留所有权利。
Cr/ceria-zirconia solid solution (Cr/CexZr1-xO2) nanoparticles with nonuniform dopant concentration as NO oxidizing catalysts were prepared via a simple, low-cost method. The preparation process utilizes aqueous phase reactions which simplifies the experimental procedure, saves the cost and leads the Ce enriched on the surface of products. The impregnation method makes the Cr enriched on the surface of products which improves the efficiency of dopant. The physicochemical characteristics were investigated by various techniques namely, XRD, Raman, BET, TEM, XPS, NO (or O-2)-TPD and UV-vis. The results demonstrated that Zr-rich sample with tetragonal structure was beneficial for the increasing of surface area and the decreasing of particle size and result in a higher adsorption capacity of NO and O-2 than Ce-rich sample. Therefore, Cr/Ce0.14Zr0.86O2 catalyst exhibited the higher activity for NO oxidation than other catalysts, which achieved 62.18% at 300 degrees C. The UV-vis analysis proved that the adsorbed NO interacted with the adsorbed O-2, obeying L-H model. The dynamics tests confirmed the above suggestion. (C) 2013 Elsevier B.V. All rights reserved.