Mg modified MnOx-CeO2-δ catalyst for low temperature complete oxidation of simulated diesel engine exhaust

• Published in: Applied surface science Vol. 502; p. 144299
• Main Authors: Lavande, N.R., More, R.K., More, P.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2020
• Subjects: Adsorbed surface oxygen; DOC; Lattice distortion; Mg-doping; Oxygen vacancies; DOC; Oxygen vacancies; Lattice distortion; Mg-doping; Adsorbed surface oxygen
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.144299

[Display omitted] •The optimized MgO-MnOxCeO2-δ catalyst showed higher CO and propene conversion.•MgO-MnOxCeO2-δ showed maximum oxidation of diesel engine exhaust.•Mg doping in MnOxCeO2-δ increases formation of Mn3+ and Ce3+ species.•Formation of highly distorted Mn-O-Ce with MgO nanorod could improve the activity. The series of Mg doped MnOxCeO2-δ were prepared by co-precipitation and investigated for complete oxidation of propene, CO and simulated diesel engine exhaust. The optimized MgO-MnOxCeO2-δ catalyst showed higher CO conversion at lower temperature (<65 °C) compared to the MnOxCeO2-δ and 1 wt% Pt/Al2O3. The MgO-MnOxCeO2-δ catalyst also showed higher activity at lower temperature under the simulated diesel engine exhaust. The catalysts were characterized by PXRD, N2 adsorption, ICP-AES, EDS, H2-TPR, XPS, O2-TPD, Raman, HRTEM techniques. The characterizations revealed the formation of MgO nanorods. MgO could be responsible for the increase in distortion of Ce lattice by forming oxygen vacancies. The Mg doped MnOxCeO2-δ catalyst showed a smaller size of Mn2O3 nanorods and increase in concentration of surface oxygen compared to the MnOxCeO2-δ catalyst. A well-dispersed MgO could be responsible for the abstraction of the proton by lowering the activation energy which resulting in the facile activation of the hydrocarbon.