Low Ag concentration Ag/CeO2 catalysts prepared with various CeO2 precursors in carbon monoxide oxidation reaction

• Published in: Catalysis letters 2024-11, Vol.154 (11), p.6144-6156
• Main Authors: Liberman, Elena Y., Suvorova, Elena I., Vasil’kov, Alexander Y., Voronova, Anastasiia A., Pereyaslavtsev, Alexander. Y., Kon’kova, Tatiana V.
• Format: Article
• Language: English
• Subjects: Adsorption; Ammonium hydroxide; Carbon monoxide; Catalysis; Catalysts; Catalytic activity; ceric oxide; Cerium oxides; Chemical synthesis; Chemistry; Chemistry and Materials Science; Chromatography; Gas chromatography; Industrial Chemistry/Chemical Engineering; Low temperature; Morphology; Nanoparticles; Nitrates; Nitrogen; Organometallic Chemistry; Oxidation; Oxidizing atmospheres; Physical Chemistry; Precipitators; Scanning electron microscopy; Silver; Spectrum analysis; Temperature; X ray photoelectron spectroscopy
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-024-04774-z

Ag/CeO 2 catalysts for the CO oxidation reaction were synthesized by the metal-vapor method. Highly dispersed cerium dioxide used as a carrier was obtained by precipitation of Ce +3 ions with various (NH 4 OH, (NH 4 ) 2 CO 3 and H 2 C 2 O 4 ) precipitators and subsequent calcination in an oxidizing atmosphere. CeO 2 particles were formed with different morphologies depending on the precipitator used. When using NH 4 OH, mainly spheroidal particles are formed, while the shape of platelets is typical for the use of H 2 C 2 O 4 . The samples were characterized by EDX, SEM, TEM, XPS, low-temperature nitrogen adsorption. Catalytic testing of the samples was carried out in an oxidation reaction using gas chromatography. It was found that the catalytic activity of the samples decreases in a series Ag/CeO 2carb  > Ag/CeO 2oxal  > Ag/CeO 2hydr. Ag/CeO 2oxal catalysts demonstrated relatively high activity and the most stable operation over 10 cycles. Graphical Abstract