Counting of Oxygen Defects versus Metal Surface Sites in Methanol Synthesis Catalysts by Different Probe Molecules

Autor:	Julia Schumann, Matthias B. Fichtl, Nikolas Jacobsen, Olaf Hinrichsen, Robert Schlögl, Martin Muhler, Igor Kasatkin, Malte Behrens
Rok vydání:	2014
Předmět:	Chemistry Thermal desorption spectroscopy Inorganic chemistry Chemie chemistry.chemical_element General Medicine General Chemistry Oxygen Catalysis Metal chemistry.chemical_compound Adsorption Chemisorption visual_art visual_art.visual_art_medium Molecule Methanol
Zdroj:	Angewandte Chemie International Edition. 53:7043-7047
ISSN:	1433-7851
DOI:	10.1002/anie.201400575
Popis:	Different surface sites of solid catalysts are usually quantified by dedicated chemisorption techniques from the adsorption capacity of probe molecules, assuming they specifically react with unique sites. In case of methanol synthesis catalysts, the Cu surface area is one of the crucial parameters in catalyst design and was for over 25 years commonly determined using diluted N2O. To disentangle the influence of the catalyst components, different model catalysts were prepared and characterized using N2O, temperature programmed desorption of H2, and kinetic experiments. The presence of ZnO dramatically influences the N2O measurements. This effect can be explained by the presence of oxygen defect sites that are generated at the Cu-ZnO interface and can be used to easily quantify the intensity of Cu-Zn interaction. N2O in fact probes the Cu surface plus the oxygen vacancies, whereas the exposed Cu surface area can be accurately determined by H2.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::6b46d63b25f498c2f912021814217525 https://doi.org/10.1002/anie.201400575 Zobrazit plný text záznamu Plný text