Bismuth Manganese Catalysts for Soot Oxidation in Diesel Engine Exhaust: Effect of Preparation Methods on Active Oxygen Species. Issue 5 (2nd February 2023)

• Record Type: Journal Article
• Authors: Li, Congcong; Wang, Jie; Dai, Wenyue; Zhang, Changsen
• Is Part Of: ChemistrySelect. Volume 8:Issue 5(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-02-02
• Subjects: Hydrolysis-driven redox -- Active oxygen species -- Soot combustion -- Manganese bismuth catalysts -- Oxygen vacancies; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.202203167
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: To manufacture efficient and cost‐effective catalysts for soot combustion, a series of Mn x BiO y catalysts with different molar ratios of manganese bismuth ( x =1, 3, 6, 9) were prepared by hydrolysis driven redox, coprecipitation and hydrothermal synthesis methods (named R−Mn x BiO y, Cop−Mn x BiO y and H−Mn x BiO y, respectively). The physicochemical properties of the as‐prepared catalysts were characterized via powder X‐ray diffraction (XRD), transmission electron microscope (TEM), temperature‐programmed reduction by hydrogen (H2 −TPR), X‐ray photoelectron spectroscopy (XPS), and so on. The catalytic performance results show that R−Mn3 BiO y catalyst obtained by hydrolysis‐driven redox method exhibited highest catalytic activity with a maximum concentration of CO2 at 390 °C (T10 =330 °C, T50 =385 °C, and T90 =425 °C). Meanwhile, the reaction mechanism of R−Mn3 BiO y catalysts was also proposed based on the characterization results. The reason for high catalytic is related to the uniform distribution of Bi on the surface of Mn, which forms more lattice defects, thereby generating a large number of oxygen vacancies and providing more active sites for catalytic reactions. This provides a reference for the design of efficient and stable soot catalysts. Abstract : Bismuth modified manganese oxides (coprecipitation, hydrothermal synthesis, hydrolysis driven redox) were synthesized by different methods. It was found that when the content of metal elements was fixed, the catalyst materials prepared by hydrolysis driven redox method have high stability and high activity for soot combustion. The reason for high catalytic is related to the uniform distribution of Bi on the surface of Mn, which forms more lattice defects and generating a large number of oxygen vacancies and providing more active sites for catalytic reactions.