In this work, a series of BaMnCuO samples (x: 1, 0.9, 0.8, and 0.7, BxMC) was synthesized, characterized, and used as catalysts for CO oxidation reaction. All formulations were active for CO oxidation in the tested conditions. A correlation between the electrical conductivity, obtained by impedance spectroscopy, and the reducibility of the samples, obtained by H-TPR, was observed. The BaMnCuO composition (B0.8MC) showed the best catalytic performance (comparable to that of the 1% Pt/AlO reference sample) during tests conducted under conditions similar to those found in the exhaust gases of current gasoline engines. The characterization data suggest the simultaneous presence of a high Mn(IV)/Mn(III) surface ratio, oxygen vacancies, and reduced copper species, these two latter being key properties for ensuring a high CO conversion percentage as both are active sites for CO oxidation. The reaction temperature and the reactant atmosphere composition seem to be the most important factors for achieving a good catalytic performance, as they strongly determine the location and stability of the reduced copper species.
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http://dx.doi.org/10.3390/nano15020103 | DOI Listing |
J Am Chem Soc
January 2025
Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
Coordinatively unsaturated copper (Cu) has been demonstrated to be effective for electrifying CO reduction into C products by adjusting the coupling of C-C intermediates. Nevertheless, the intuitive impacts of ultralow coordination Cu sites on C products are scarcely elucidated due to the lack of synthetic recipes for Cu with low coordination numbers and its vulnerability to aggregation under reductive potentials. Herein, computational predictions revealed that Cu sites with higher levels of coordinative unsaturation favored the adsorption of C and C intermediates.
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January 2025
Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3., 1111 Budapest, Hungary.
A series of α-hydroxy-alkylphosphonates and α-hydroxy-alkylphosphine oxides were synthesized by the Pudovik reaction of acetaldehyde and acetone with dialkyl phosphites or diarylphosphine oxides. The additions were performed in three different ways: in liquid phase using triethylamine as the catalyst (1), on the surface of AlO/KF solid catalyst (2), or by a MW-assisted NaCO-catalyzed procedure (3). In most of the cases, our methods were more efficient and more robust than those applied in the literature.
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January 2025
Department of Physical Chemistry, Plovdiv University "Paisii Hilendarski", 24, Tzar Assen Str., 4000 Plovdiv, Bulgaria.
Lipid peroxidation is a major process that determines the quality of various oil samples during their use and storage, in which the primary products are hydroperoxides (HP'). HP' are very stable compounds at ambient conditions and are harmful to human health. Therefore, the evaluation of the degree of oil oxidation is an excellent tool for ensuring food safety.
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January 2025
Faculty of Chemistry, Jagiellonian University in Krakow, Gronostajowa 2, 30-387 Krakow, Poland.
The removal of soot particles via high-performance catalysts is a critical area of research due to the growing concern regarding air pollution. Among various potential catalysts suitable for soot oxidation, cerium oxide-based materials have shown considerable promise. In this study, CeO samples obtained using a range of preparation methods (including hydrothermal synthesis (HT), sonochemical synthesis (SC), and hard template synthesis (TS)) were tested in soot combustion.
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January 2025
Department of Chemical Technology, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University, 3 Maria Curie-Skłodowska Square, 20-031 Lublin, Poland.
The reaction mechanism of soot oxidation on Mn (MnO), Mn-Ce (MnO-CeO), and Ce (CeO) catalysts in tight contact conditions was investigated using ITKA (isotopic transient kinetic analysis). The obtained results suggest that lattice-bulk oxygen from all studied catalysts takes part in the soot oxidation process but with varying relative contributions: for the Ce catalyst, this contribution is practically 100%, whereas with decreasing Ce content in Mn-Ce catalysts, the significance of lattice-bulk oxygen for soot oxidation diminishes. For the Mn catalyst, it is estimated to be below 50%.
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