The recycling of CO₂ back into chemicals via photo-electrochemical cells represents a viable route to mitigate the global climate crisis of current days. In this paper we focus on the copper-iron delafossite oxide, CuFeO₂, which has been proven to have suitable physico-chemical properties to photo-catalyze the carbon dioxide reduction to formic acid. The specific electronic and structural features that allow activating the highly stable CO₂ molecule are dissected by exploiting state-of-the art first principles methods. The effects of surface oxygen vacancies as well as the different roles of copper and iron on the adsorption and the activation of carbon dioxide at the CuFeO₂ most stable surface are analyzed. These results highlight the key role of oxygen defects in favoring the CO₂ adsorption and in promoting the formation of a radical anion CO₂⁻ or a carbonate-like adsorbate so providing the scientific grounds for implementing new rational design strategies and improving the performances of CuFeO₂-based photoelectrodes for CO₂ reduction.

通过光电化学电池将CO ₂再循环回化学物质中，是缓解当今全球气候危机的一条可行途径。在本文中，我们重点研究铜-铁铜铁矿氧化物CuFeO ₂，已证明其具有合适的物理化学性质，可以光催化将二氧化碳还原为甲酸。通过利用最先进的第一原理方法来剖析允许激活高度稳定的CO ₂分子的特定电子和结构特征。表面氧空位的影响以及铜和铁在CuFeO ₂上对二氧化碳的吸附和活化的不同作用分析最稳定的表面。这些结果强调在有利于CO氧缺陷的关键作用₂吸附和促进自由基阴离子形成CO ₂ ^-或碳酸盐状吸附从而提供用于实现新的合理的设计策略的科学依据和改善CuFeO的性能用于减少CO _2的基于₂的光电极。