Cui Meisheng, Hou Yongke, Zhai Zhizhe, Zhong Qiang, Zhang Yongqi, Huang Xiaowei
National Engineering Research Center for Rare Earth Materials, General Research Institute for Nonferrous Metals No. 2, Xinjiekou Wai Street, Haidian District Beijing 100088 PR China
Grirem Advanced Materials Co., Ltd. No. 43, Beisanhuan Middle Road Beijing 100088 PR China.
RSC Adv. 2019 Mar 12;9(14):8081-8090. doi: 10.1039/c9ra01048c. eCollection 2019 Mar 6.
The unique reversible oxygen storage and release capacity of cerium zirconium mixed oxides makes them ideal washcoat materials of automotive three-way catalysts (TWC). In this work, cerium zirconium mixed oxides of CeZrLaNdO were prepared a co-precipitation method. The effects of hydrogen peroxide co-precipitation and inert N atmosphere calcination on the structure and properties of cerium zirconium mixed oxides were investigated systematically by Brunauer-Emmett-Teller surface area measurements, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, hydrogen temperature-programmed reduction, oxygen storage capacity (OSC), Raman spectroscopy, and X-ray photoelectron spectroscopy. Additionally, the catalytic performance of palladium supported catalysts was studied. Results show that hydrogen peroxide co-precipitation promotes the dispersion of cerium zirconium particles and enhances crystal grain growth, resulting in good thermal stability of the obtained cerium zirconium mixed oxides. Inert N atmosphere calcination also enhances the dispersion of particles, results in smaller and finer crystal grains, enriches pore channels, and significantly improves the surface area, pore volume and OSC, with an OSC of 424.57 μmolO g, which is a 13.37% increment compared with the common sample. The benefits of hydrogen peroxide co-precipitation and inert N atmosphere calcination endow the Pd supported catalysts of cerium zirconium mixed oxides with good three-way catalytic performance.
铈锆复合氧化物独特的可逆储氧和释氧能力使其成为汽车三效催化剂（TWC）理想的涂层材料。在本工作中，采用共沉淀法制备了CeZrLaNdO铈锆复合氧化物。通过Brunauer-Emmett-Teller比表面积测量、X射线衍射、扫描电子显微镜、透射电子显微镜、氢气程序升温还原、储氧能力（OSC）、拉曼光谱和X射线光电子能谱等手段，系统研究了过氧化氢共沉淀和惰性N气氛煅烧对铈锆复合氧化物结构和性能的影响。此外，还研究了钯负载催化剂的催化性能。结果表明，过氧化氢共沉淀促进了铈锆颗粒的分散，增强了晶粒生长，使得所制备的铈锆复合氧化物具有良好的热稳定性。惰性N气氛煅烧也增强了颗粒的分散性，使晶粒更小更细，丰富了孔道，显著提高了比表面积、孔容和OSC，OSC为424.57 μmolO g，与普通样品相比提高了13.37%。过氧化氢共沉淀和惰性N气氛煅烧的优点赋予了铈锆复合氧化物负载钯催化剂良好的三效催化性能。
