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Abstract
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The potential of Al- and Ga-doped graphene (Al–Gr/Ga–Gr) to activate the C–H bond of CH4 by N2O
to generate methanol is explored using density functional theory calculations. Both surfaces have a
higher affinity for capturing N2O than CH4. The oxidation of CH4 starts with the decomposition of N2O
into N2 and Oads species, followed by a hydrogen transfer from CH4 to Oads, resulting in CH3 and HOads
species. Our results demonstrate that CH3 combining with HOads to yield CH3OH needs only 0.18 eV on
Al–Gr, which is 0.11 eV lower than on Ga–Gr. On the other hand, the competing CO oxidation reaction
(CO + Oads - CO2) is inhibited over the Ga–Gr because of its greater activation barrier than the CH4
oxidation process. These findings may provide valuable information for fine-tuning the catalytic activity
of graphene-based materials in low-temperature partial oxidation of CH4.
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