通過理論計算研究氧化銅材料上二氧化碳還原的電催化反應。在先前的文獻中，使用混合價態的銅氧化物作為催化劑容易發生一氧化碳的二聚化反應，這些材料包括氧化銅和氧化亞銅，後者是本研究的重點。 首先，通過觀察隨著氧空缺濃度增加而造成的形成能變化，對三個不同的表面做塞選，分別為Cu2O （100），Cu2O（110）和Cu2O（111）表面。 我們發現Cu2O（110）表面在所有考慮的表面中最為穩定。此外，我們研究了C-C偶聯反應性與Cu2O（110）的氧空缺之間的相關性。我們發現，當表面的Cu+ / Cu0的比例為1：1時，上述反應最有可能發生，能障為0.71eV，為-0.37eV放熱反應。且也解釋了為何在氧化銅衍生物表面的對於乙醇有較高的產物選擇性。

The electrochemical reduction of CO2 (CO2RR) on copper oxide materials is investigated by theoretical calculations. In literature, C2 dimerization occurs readily with mixed valence copper oxides as catalyst, these materials include CuO and Cu2O, the latter of which is the focus of this study. First, three different surfaces, Cu2O (100), Cu2O (110), and Cu2O (111) were screened for stability, by observing the variation of formation energy as the amount of vacancies changed. We discovered that the Cu2O (110) surface the most stable among the surfaces considered. Furthermore, we examined the correlation between the reactivity of C-C coupling and the oxygen vacancies of Cu2O (110). We found that the aforementioned reaction is most likely to occur when the ratio of Cu0/Cu+1 is 1:1, with the energy barrier at 0.71eV, with a ΔE of -0.37eV. We also explain why there is a higher product selectivity for ethanol on the surface of the copper oxide derivative.

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