A rational design of an electrocatalyst presents a promising avenue for solar fuels synthesis from carbon dioxide (CO2) fixation but is extremely challenging. Herein, we use density functional theory calculations to study an inexpensive binary copper-iron catalyst for photoelectrochemical CO2 reduction toward methane. The calculations of reaction energetics suggest that Cu and Fe in the binary system can work in synergy to significantly deform the linear configuration of CO2 and reduce the high energy barrier by stabilizing the reaction intermediates, thus spontaneously favoring CO2 activation and conversion for methane synthesis. Experimentally, the designed CuFe catalyst exhibits a high current density of -38.3 mA⋅cm-2 using industry-ready silicon photoelectrodes with an impressive methane Faradaic efficiency of up to 51%, leading to a distinct turnover frequency of 2,176 h-1 under air mass 1.5 global (AM 1.5G) one-sun illumination.

中文翻译：

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高效的二元铜铁催化剂，用于将光电化学二氧化碳还原为甲烷。

电催化剂的合理设计为从二氧化碳（CO2）固定合成太阳能燃料提供了有希望的途径，但极具挑战性。本文中，我们使用密度泛函理论计算来研究一种廉价的二元铜铁催化剂，用于光电化学将CO2还原为甲烷。反应能的计算表明，二元体系中的铜和铁可以协同作用，通过稳定反应中间体来显着地改变CO2的线性构型并降低高能垒，从而自发地促进CO2的活化和转化以进行甲烷合成。在实验上，设计的CuFe催化剂使用工业就绪的硅光电极表现出-38.3 mA·cm-2的高电流密度，甲烷法拉第效率高达51％，