In situ construction of heteroatom F-doped Mn3O4 spinel catalysts with robust activity and SO2 resistance for NH3-SCR at low temperature

• Published in: Applied catalysis. B, Environmental Environmental, 2023-12, Vol.338, p.123086, Article 123086
• Main Authors: Chen, Chong, Wang, Yunxia, Li, Junxi, Tian, Fengyu, Chen, Weijuan, Feng, Chao, Pan, Yuan, Liu, Yunqi
• Format: Article
• Language: English
• Subjects: Electron transfer; F-doped Mn3O4; MOFs; NH3-SCR; SO2 resistance
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2023.123086

Herein, we propose a novel in situ construction method of F-doped Mn3O4 catalysts through a crystallization-pyrolysis-oxidation strategy. The F-Mn3O4-3 % exhibits a NO conversion above 90 % from 150° to 310°C at an ultra-high GHSV of 400,000 h−1. The SO2 resistance is also significantly improved compared to pure Mn3O4. Doping of Mn3O4 with F increases the surface acidity and tunes the electronic properties of the catalysts. The increase of acid sites not only facilitates the adsorption of NH3 species, thereby improving NH3-SCR activity, but also inhibits SO2 adsorption on the catalyst surface. The electron conduction between SO2 and Mn3+ can also be effectively inhibited after F replaces O, resulting in the F-doped Mn3O4 catalysts can selectively oxidizing NO to NO2 rather than oxidizing SO2 to SO3, thereby causing the decrease of sulfate species. Our work provides a novel idea for the design of SCR catalysts with high activity and SO2 resistance. [Display omitted] •F-doped Mn3O4 spinel catalysts were thermally derived from MOFs.•F-dopant enhanced the catalytic activity of Mn3O4 during NH3-SCR reaction at ultra-high GHSV.•F-dopant significantly improved the SO2 resistance compared to Mn3O4.•The role of F in improving the SO2 resistance and NH3-SCR activity is revealed.