Unravelling the Enigma of Nonoxidative Conversion of Methane on Iron Single‐Atom Catalysts

Autor:	Wan-Lu Li, Chun-Ran Chang, Jin-Cheng Liu, Zeng-Hui Duan, Tian-Yu Zhang, Yang-Gang Wang, Yuan Liu, Hai Xiao, Jun Li, T. T. Li, Ming Yan
Rok vydání:	2020
Předmět:	Reaction mechanism Ethylene 010405 organic chemistry chemistry.chemical_element General Chemistry 010402 general chemistry Photochemistry 01 natural sciences Catalysis Methane 0104 chemical sciences Active center chemistry.chemical_compound chemistry Desorption Atom Carbon
Zdroj:	Angewandte Chemie International Edition. 59:18586-18590
ISSN:	1521-3773 1433-7851
DOI:	10.1002/anie.202003908
Popis:	The direct, nonoxidative conversion of methane on a silica-confined single-atom iron catalyst is a landmark discovery in catalysis, but the proposed gas-phase reaction mechanism is still open to discussion. Here, we report a surface reaction mechanism by computational modeling and simulations. The activation of methane occurs at the single iron site, whereas the dissociated methyl disfavors desorption into gas phase under the reactive conditions. In contrast, the dissociated methyl prefers transferring to adjacent carbon sites of the active center (Fe1 ©SiC2 ), followed by C-C coupling and hydrogen transfer to produce the main product (ethylene) via a key -CH-CH2 intermediate. We find a quasi Mars-van Krevelen (quasi-MvK) surface reaction mechanism involving extracting and refilling the surface carbon atoms for the nonoxidative conversion of methane on Fe1 ©SiO2 and this surface process is identified to be more plausible than the alternative gas-phase reaction mechanism.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::941eab946824e00142bf06f129f88fb0 https://doi.org/10.1002/anie.202003908 Zobrazit plný text záznamu Plný text