首页|Investigation of Ce/BEA as a passive NOx adsorber:1.The occurrences of cerium and adsorption behavior

Investigation of Ce/BEA as a passive NOx adsorber:1.The occurrences of cerium and adsorption behavior

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
Ce/BEA has great potential as a passive NOx absorber(PNA)to reduce the NOx emissions during the cold start phase especially in diesel engine for its high resistance to CO and suitable NOx desorption tem-perature range.However,as a novel material,its physical and chemical properties still remain unknown.In this work,Ce/BEA was synthesized by ion-exchange method to identify the active species in NOx adsorption,compared with aggregated Ce species in Ce/SiAlOx prepared by impregnation method.X-ray diffraction(XRD),high resolution-transmission electron microscopy(HR-TEM)and aberration-corrected-scanning transmission electron microscopy(AC-STEM)were performed to confirm the isolated single atom formation of Ce species in Ce/BEA.UV-vis diffraction reflection spectra(DRS)and X-ray photo-electron spectroscopy(XPS)were conducted to find the difference of chemical environment between the isolated Ce species and aggregated ones.PNA performance evaluation and temperature programmed reduction of hydrogen(H2-TPR)results show the high NOx storage capacity and active oxygen species quantity in Ce/BEA.It is also found that the main NOx adsorption species are Ce4+-O*rather than Ce3+.NOx-diffuse reflectance infrared Fourier transform spectroscopy(NOx-DRIFTS)confirms that the biden-tate nitrite species are the critical NOx adsorption intermediates and the conception of NOx adsorption and desorption processes is proposed.

Passive NOx absorberCe/BEAIsolated Ce speciesRare earths

Minghui Yu、Yiying Ding、Xiaojie Yu、Siwei Yan、Meiqing Shen、Jianqiang Wang、Jun Wang、Gurong Shen

展开 >

School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China

School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China

School of Chemical Engineering and Technology,Tianjin University,Tianjin,300350,China

National Rare Earth Catalysis Research Institute,Dongying,257000,China

展开 >

National Key R&D Program of ChinaInnovative Research Groups of the National Natural Science Foundation of ChinaYoung Elite Scientists Sponsorship Program by CASTKey R&D project of Shandong ProvinceKey R&D project of Shandong Province

2021YFB3503200519210042021QNRC0012021CXGC0107032022CXGC020311

2024

10.1016/j.jre.2023.06.005

稀土学报(英文版)
中国稀土学会

稀土学报(英文版)

CSTPCDEI
影响因子：1.3
ISSN：1002-0721
年,卷(期)：2024.42(7)