In this paper, we investigated the role of excited-state hydrogen bonding in the photocatalytic carbon dioxide reduction reaction (CO₂RR) utilizing Rose Bengal as a catalyst, through a combined experimental and theoretical approach. Experiments validated the successful conversion of CO₂ to CO in a homogeneous aqueous solution system under light irradiation, without additional photosensitizers or sacrificial agents. Theoretically, the DFT/TDDFT calculations modeled the catalyst-reactants as a hydrogen-bonded complex (HBC), understanding the energy, hydrogen, and electron transfer mechanisms induced by excited-state hydrogen bonding. Combining the photophysical and photochemical insights revealed the complete catalytic cycle, identifying the water oxidation process as the rate-limiting step in the entire photocatalytic CO₂RR process. Experimental and computational results provide molecular-level insights into the structure–activity relationships. This work enhances comprehension of the pivotal role of excited-state hydrogen bonding and holds significant reference value for enhancing the conversion efficiency in the photocatalytic CO₂RR.

中文翻译：

---

揭示激发态氢键在均相光催化二氧化碳还原中的关键作用

在本文中，我们通过实验和理论相结合的方法，研究了激发态氢键在利用玫瑰红作为催化剂的光催化二氧化碳还原反应（CO ₂ RR）中的作用。实验验证了在光照射下均质水溶液体系中CO ₂成功转化为CO，无需额外的光敏剂或牺牲剂。理论上，DFT/TDDFT 计算将催化剂反应物建模为氢键配合物 (HBC)，了解激发态氢键诱导的能量、氢和电子转移机制。结合光物理和光化学的见解揭示了完整的催化循环，将水氧化过程确定为整个光催化CO ₂ RR过程中的限速步骤。实验和计算结果提供了对结构-活性关系的分子水平见解。该工作增强了人们对激发态氢键关键作用的理解，对于提高光催化CO ₂ RR的转化效率具有重要的参考价值。