Bismuth oxyhalides (Bi_mO_nX_p, where X represents Cl, Br, and I) present a promising family of template catalysts for in situ Bi₂O₂CO₃ synthesis to achieve the highly efficient CO₂ electrochemical reduction reaction (CO₂RR) toward formate. However, the specific mechanism behind Bi_mO_nX_ps' structural reconstruction and their subsequent effects on CO₂RR performance remain unresolved inquiries. In this study, a comprehensive investigation into how halogens (Cl, Br, and I) influence Bi_mO_nX_p CO₂RR performance was conducted. It is suggested that Br is capable of introducing a bismuth-rich phase (Bi₂₄O₃₁Br₁₀) in BiOBr, which promotes the formation of external Bi–O structural characteristics and leads to exceptional CO₂RR performance, with a faradaic efficiency (FE_HCOO⁻) of 90.67% and a formate partial current density (J_HCOO⁻) of 52.31 mA cm⁻², surpassing those of BiOCl and BiOI. Kinetic simulations suggest that the alternative Bi–O structure will promote the combination of the Bi–O structure and carbon-based intermediates, leading to the improved kinetics of the rate-determining step, and ultimately resulting in better CO₂RR performance.

中文翻译：

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BimOnBrp 衍生的 Bi2O2CO3 中卤化物引导的碳亲和活性位点可有效电催化 CO2 还原为甲酸盐


卤氧化铋（Bi _m O _n X _p ，其中 X 代表 Cl、Br 和 I）是一类很有前途的模板催化剂，用于原位合成Bi ₂ O ₂ CO ₃ ，以实现高效的 CO ₂电化学还原反应（CO ₂ RR) 朝向甲酸盐。然而，B _m O _n X _p s结构重构背后的具体机制及其对CO ₂ RR性能的后续影响仍然悬而未决。在本研究中，对卤素（Cl、Br 和 I）如何影响 Bi _m O _n X _p CO ₂ RR 性能进行了全面研究。 研究表明，Br能够在BiOBr中引入富铋相（Bi ₂₄ O ₃₁ Br ₁₀ ），从而促进外部Bi-O结构特征的形成，并导致优异的CO ₂ RR性能，并具有法拉第效率（ FE _{HCOO ^-} ）为90.67%，甲酸盐部分电流密度（ J _{HCOO ^-} ）为52.31 mA cm ^-2 ，超过了BiOCl和BiOI。动力学模拟表明，替代的Bi-O结构将促进Bi-O结构与碳基中间体的结合，从而改善速率决定步骤的动力学，并最终获得更好的CO ₂ RR性能。