Effect of Fe doping on NH3 adsorption and resistance to sulfur poisoning on the surface of β-MnO2 (110): a DFT-D study

• Published in: Journal of materials science Vol. 57; no. 39; pp. 18468 - 18485
• Main Authors: Liu, Yafang, Zhu, Baozhong, Chen, Jiuyu, Sun, Yunlan, Xu, Minggao
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.10.2022; Springer Nature B.V
• Subjects: Adsorption; Ammonia; Ammonium sulfate; Catalysts; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Crystallography and Scattering Methods; Doping; Electronic Materials; Industrial applications; Iron; Low temperature; Manganese dioxide; Materials Science; Oxidation; Poisoning; Polymer Sciences; Solid Mechanics; Sulfur; Sulfur dioxide; Surface chemistry
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-022-07740-5

Manganese-based catalysts have a good low-temperature deNO x activity, but the presence of SO 2 can cause their poisoning and deactivation, limiting their industrial use. They have been discovered to be more sulfur resistant when iron (Fe) is added. However, the mechanism of Fe as a doping additive to enhance manganese-based catalysts’ sulfur resistance is not clear. During this study, the impact of Fe doping for gas adsorption and anti-sulfur poisoning on the β-MnO 2 (110) was investigated by using the DFT-D3 calibration. The results indicate that Fe doping promotes the adsorption of NH 3 on the Mn sites over the β-MnO 2 (110) surface, weakens SO 2 adsorption capacity, and the oxidation of SO 2 is limited. In addition, Fe doping promotes the decomposition of ammonium sulfate on the catalyst surface and alleviates its blockage of catalytic sites on the catalyst surface. This study can complement the understanding of the anti-sulfur mechanism of Mn-based catalysts and has great significance for the guidance of the design of Mn-based catalysts with good anti-sulfur poisoning.