Tailor the crystal planes of MIL-101(Fe) derivatives to enhance the activity of SCR reaction at medium and low temperature

Guozhen Qin; Jianfeng Zheng; Yifan Li; Yatao Yang; Xingmin Liu; Xiaojin Han; Zhanggen Huang

doi:10.1016/j.jcis.2022.01.147

Tailor the crystal planes of MIL-101(Fe) derivatives to enhance the activity of SCR reaction at medium and low temperature

J Colloid Interface Sci. 2022 Jun:615:432-444. doi: 10.1016/j.jcis.2022.01.147. Epub 2022 Jan 25.

Authors

Guozhen Qin¹, Jianfeng Zheng², Yifan Li¹, Yatao Yang¹, Xingmin Liu¹, Xiaojin Han³, Zhanggen Huang⁴

Affiliations

¹ State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 P. R. China; University of Chinese Academy of Sciences Beijing 10049 P. R. China.
² State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 P. R. China.
³ State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 P. R. China. Electronic address: hanxj@sxicc.ac.cn.
⁴ State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 P. R. China. Electronic address: zghuang@sxicc.ac.cn.

PMID: 35149355
DOI: 10.1016/j.jcis.2022.01.147

Abstract

Mainly exposed crystal facets and controllable morphology play a key role in the final performance of the preparation of specific nanomaterials. In the present study, a metal-organic framework pyrolysis method without adding solvent modifiers was developed. By adding CO in the calcination atmosphere to change atmosphere ratio, Fe₃O₄ nanostructures are exposed with different crystal planes and evaluated their performance in NH₃-SCR reaction. This study proves that SCR catalytic activity of Fe₃O₄ nanocrystals is dependent on morphology and crystal facet. Compared with materials exposed (100), catalysts with more (111) show stronger deNO_x performance. The preferential exposure of Fe₃O₄ (111) crystal facets increases the concentration of adsorbed oxygen on the catalyst, showing higher surface acidity, and enhances the interaction among NO, O₂ and catalyst, which is conducive to SCR reaction. This is supported by DFT calculations. The results present a great application prospect in preparing nanomaterials with specific crystal structures to effectively treat pollutants.

Keywords: Exposed facets; Fe(3)O(4); Metal-organic framework; SCR, DFT.