It is still a great challenge to achieve high selectivity of CH₄ in CO₂ electroreduction reactions (CO₂RR) because of the similar reduction potentials of possible products and the sluggish kinetics for CO₂ activation. Stabilizing key reaction intermediates by single type of active sites supported on porous conductive material is crucial to achieve high selectivity for single product such as CH₄. Here, Cu₂O(111) quantum dots with an average size of 3.5 nm are in situ synthesized on a porous conductive copper‐based metal–organic framework (CuHHTP), exhibiting high selectivity of 73 % towards CH₄ with partial current density of 10.8 mA cm⁻² at −1.4 V vs. RHE (reversible hydrogen electrode) in CO₂RR. Operando infrared spectroscopy and DFT calculations reveal that the key intermediates (such as *CH₂O and *OCH₃) involved in the pathway of CH₄ formation are stabilized by the single active Cu₂O(111) and hydrogen bonding, thus generating CH₄ instead of CO.

中文翻译：

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通过在导电MOF上原位生成的Cu2O单型位点，将高选择性的CO2电还原为CH4：稳定具有氢键的关键中间体。

在CO ₂电还原反应（CH ₂ RR）中实现CH _4的高选择性仍然是一个巨大的挑战，因为可能的产物具有相似的还原电势，并且活化CO _2的反应动力学缓慢。通过负载在多孔导电材料上的单一类型的活性位点来稳定关键反应中间体，对于获得单一产品（例如CH _4）的高选择性至关重要。在此，在多孔导电铜基金属有机框架（CuHHTP）上原位合成平均尺寸为3.5 nm的Cu ₂ O（111）量子点，对CH ₄表现出73％的高选择性，且部分电流密度为10.8 mA厘米^-2在-1.4 V相对于CO ₂ RR中的RHE（可逆氢电极）的情况。Operando红外光谱和DFT计算表明，CH ₄形成途径中涉及的关键中间体（例如* CH ₂ O和* OCH ₃）通过单个活性Cu ₂ O（111）和氢键得以稳定，从而生成CH ₄代替CO。