We investigated the oxidation of formaldehyde, one of the major indoor air pollutants, into CO2 and H2O over Fe atoms trapped in defects on graphene by first-principles based calculations. These trapped Fe atoms are not only stable to withstand interference from the reaction environments but are also efficient in catalyzing the reactions between coadsorbed O-2 and formaldehyde. The oxidation of formaldehyde starts with the formation of a peroxide-like intermediate and continues by its dissociation into. eta(1)-OCHO coadsorbed with an OH radical. Then, the adsorbed OCHO undergoes conformational changes and hydride transfer, leading to the formation of H2O and CO2. Subsequent adsorption of O2 or formaldehyde facilitates desorption of H2O and a new reaction cycle initiates. The calculated barriers for formation and dissociation of the peroxide-like intermediate are 0.43 and 0.40 eV, respectively, and those for conformation changes and hydride transfer are 0.47 and 0.13 eV, respectively. These relatively low barriers along the reaction path suggest the potential high catalytic performance of trapped Fe atoms for formaldehyde oxidation.
|Original language||English (US)|
|Number of pages||10|
|Journal||Catal. Sci. Technol.|
|State||Published - 2017|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This work was supported by the NSFC (21573034, 21373036 and 21103015), the Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (second phase, No: NSFC2015_65 and NSFC2015_66), the Fundamental Research Funds for the Central Universities (DUT15LK18, DUT14LK09 and DUT12LK14) and the Special Academic Partner GCR Program from the King Abdullah University of Science and Technology. X. L. would also like to thank the Universite Paris-Est for the visiting professorship. The supercomputer time was provided by the National Supercomputing Center in Guangzhou, China, the Supercomputing Core Laboratory at the King Abdullah University of Science and Technology and the High Performance Computing Center, Dalian University of Technology.