A DFT study on the copper-single-atom modified 2D electride Ca2N monolayer for ethanol dehydrogenation

Two-dimensional (2D) electrides, with electrons confined in interlayer spaces instead of at atomic proximities, have received considerable attention due to their exotic properties. However, the current exploration of electrides in the field of catalysis urgently needs to be expanded. Here, we report novel thermodynamically stable Cu single-atom-modified 2D electride Ca2N monolayer catalysts for ethanol dehydrogenation using density functional theory calculations. The interaction and synergistic catalytic mechanism of copper single atoms and Ca2N monolayers were thoroughly revealed. The coordination environment of copper greatly affects the reaction sites for ethanol dehydrogenation. Furthermore, it was found that the strong electron transfer ability of Ca2N monolayer promoted the adsorption and activation of ethanol molecules on the catalyst, resulting in a cleavage energy barrier of the O–H bond as low as 0.29 eV on Cu1/Ca2N. Furthermore, turnover frequency (TOF) analysis demonstrates that Cu1/Ca2N exhibits significantly higher activity compared to Ca2N with lower energetic span (δE) of 2.52 eV at 298.15 K for the cycle of ethanol dehydrogenation to acetaldehyde. Our work demonstrates a new avenue to the discovery of 2D electride-based catalysts and provides new insights into the mechanism of ethanol dehydrogenation.