Electrochemical CO₂ reduction into value‐added liquid fuels using CO₂ neutral renewable energy sources is very promising to solve climatic issues. In order to realize their practical applications, highly active and inexpensive electrocatalysts are urgently required. In this study, we have experimentally achieved high electrocatalytic activity towards CO₂ reduction for the synthesis of formate with an enhanced current density of 15.1 mA·cm^–2 and significantly improved Faradaic efficiency of 98.4% upon electrochemical reduced ultrathin bismuth oxybromide nanosheets. Moreover, the stable performance during 24 h of operation is also obtained. Furthermore, by detecting the exposed crystal plane after surface reorganization and applying density functional theory calculations, the possible reaction pathways and catalytic active plane of the derived bismuth catalyst are put forward, which would offer basic and design principles to directly develop the optimized metal Bi catalysts for enhanced electrocatalytic CO₂ conversion to formate.

中文翻译：

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具有高选择性和高密度密度的用于还原CO2的金属卤氧化物的结构优化

电化学CO ₂还原成CO使用增值的液体燃料₂中性的可再生能源是非常有前途的解决气候问题。为了实现其实际应用，迫切需要高活性和廉价的电催化剂。在这项研究中，我们通过实验实现了对CO ₂还原的高电催化活性，以合成甲酸，电流密度提高了15.1 mA·cm ^–2电化学还原超薄氧溴化铋纳米片后，法拉第效率提高了98.4％。此外，还可以获得24小时运行期间的稳定性能。此外，通过检测表面重组后暴露的晶面并应用密度泛函理论计算，提出了衍生的铋催化剂的可能的反应途径和催化活性面，为直接开发优化的金属铋催化剂提供了基础和设计原理。用于增强电催化将CO ₂转化为甲酸。