Unveiling the Surface Chemical Reactions during Multi-Phase Catalytic Oxidation of Soot on Nanoengineering/Interfacing/Doping-Prepared Mn-CeO2 Catalysts Using TG-MS and Operando DRIFTS-MS

Yan Sun; Shiyu Fang; Jiacheng Xu; Tiantian Zhang; Zuliang Wu; Jing Li; Erhao Gao; Wei Wang; Lianxin Dai; Weihua Liu; Buhe Zhang; Junwei Zhang; Shuiliang Yao; Jiali Zhu

doi:10.1021/acs.langmuir.3c02409

Unveiling the Surface Chemical Reactions during Multi-Phase Catalytic Oxidation of Soot on Nanoengineering/Interfacing/Doping-Prepared Mn-CeO₂ Catalysts Using TG-MS and Operando DRIFTS-MS

Langmuir. 2023 Nov 7;39(44):15773-15784. doi: 10.1021/acs.langmuir.3c02409. Epub 2023 Oct 26.

Authors

Yan Sun¹, Shiyu Fang¹, Jiacheng Xu^{1

2}, Tiantian Zhang¹, Zuliang Wu^{1

3}, Jing Li^{1

3}, Erhao Gao^{1

3}, Wei Wang^{1

3}, Lianxin Dai⁴, Weihua Liu⁴, Buhe Zhang⁴, Junwei Zhang⁴, Shuiliang Yao^{1

2

3}, Jiali Zhu^{1

3}

Affiliations

¹ School of Environmental Science and Engineering, Changzhou University, Changzhou 213164, China.
² School of Material Science and Engineering, Changzhou University, Changzhou 213164, China.
³ Key Laboratory of Advanced Plasma Catalysis Engineering for China Petrochemical Industry, Changzhou 213164, China.
⁴ Jiangxi Xintai Functional Materials Technology Co., Ltd., Ji'an, Jiangxi 343100, China.

PMID: 37883132
DOI: 10.1021/acs.langmuir.3c02409

Abstract

The aerosol pyrolysis method from nitrate precursors was used to prepare the Mn-CeO₂ catalyst containing Mn₂O₃, CeO₂, and Mn-doped CeO₂ nanoparticles for catalyzing carbonous soot oxidation. The prepared Mn-CeO₂ catalysts have high specific surface areas, Ce³⁺ ratio, and oxygen vacancy defects; these are a benefit for soot oxidation. The T₅₀ for soot oxidation on the 0.57Mn-CeO₂ catalyst is as low as 355 °C, which is 329 °C lower than that for soot oxidation without a catalyst. The catalysts were characterized using XRD, SEM-EDS, HRTEM, XPS, Raman spectroscopy, H₂-TPR-MS, O₂-TPD-MS, soot-TPR-MS, and operando DRIFTS-MS. The functions of Mn₂O₃, CeO₂, and Mn-doped CeO₂ in the 0.57Mn-CeO₂ catalyst are unveiled. Mn-doped CeO₂ plays a key role and CeO₂ participates in soot oxidation, while Mn₂O₃ is used to enhance higher ratios of Ce³⁺, via the reaction of Mn³⁺ + Ce⁴⁺ = Mn⁴⁺ + Ce³⁺. The mechanism of soot oxidation on Mn-CeO₂ was proposed.