Methane-to-Methanol on Mononuclear Copper(II) Sites Supported on Al2O3: Structure of Active Sites from Electron Paramagnetic Resonance

Autor: Meyet, Jordan, Ashuiev, Anton, Noh, Gina, Newton, Mark A., Klose, Daniel, Searles, Keith, van Bavel, Alexander P., Horton, Andrew D., Jeschke, Gunnar, van Bokhoven, Jeroen A., Copéret, Christophe
Jazyk: angličtina
Rok vydání: 2021
Zdroj: Angewandte Chemie. International Edition, 60 (29)
ISSN: 1433-7851
1521-3773
0570-0833
Popis: The selective conversion of methane to methanol remains one of the holy grails of chemistry, where Cu-exchanged zeolites have been shown promote this reaction under stepwise conditions. Over the years, several active sites have been proposed, ranging from mono-, di- to trimeric CuII. Herein, we report the formation of well-dispersed monomeric CuII species supported on alumina using surface organometallic chemistry and their reactivity towards the selective and stepwise conversion of methane to methanol. Extensive studies using various transition alumina supports combined with spectroscopic characterization, in particular electron paramagnetic resonance (EPR), show that the active sites are associated with specific facets, which are typically found in γ- and η-alumina phase, and that their EPR signature can be attributed to species having a tri-coordinated [(Al2O)CuIIO(OH)]− T-shape geometry. Overall, the selective conversion of methane to methanol, a two-electron process, involves two monomeric CuII sites that play in concert.
Angewandte Chemie. International Edition, 60 (29)
ISSN:1433-7851
ISSN:1521-3773
ISSN:0570-0833
Databáze: OpenAIRE
Externí odkaz: