北京化工大学刘宾团队近日揭示了原子工程吖啶衍生物作为无金属和自敏化催化剂具有高效和近乎完美的选择性。相关论文发表在2025年6月3日出版的《德国应用化学》杂志上。

实现高效和选择性的光驱动二氧化碳转化为甲酸是一项重大的科学挑战，特别是在利用纯有机、无金属和富含地球元素的分子光催化剂时。

研究组首次报道了吖啶衍生物（DADN、PXZN、PTZN）的发现，它们是一种新型的无金属自敏化分子催化剂，在太阳能驱动的二氧化碳还原为甲酸方面具有卓越的性能。值得注意的是，原子工程含硫杂环PTZN在使用1,3-二甲基-1H-苯并[d]咪唑-3-鎓（BI⁺）作为质子和电子中继的光催化系统中显示出前所未有的47.8 mmol g^-1 h^-1的甲酸盐收率和>99%的选择性。 

PTZN的优越活性源于其强大的CO₂结合亲和力（-0.195 eV）、延长的电荷分离态（11 ns）和强大的CO₂电子耦合（2.51 eV）的协同组合。包括原位电子自旋共振、原位红外和瞬态吸收光谱在内的综合研究明确揭示了从激发的单线态吖啶衍生物到CO₂的直接单电子转移过程，从而产生CO₂·^-。此外，利用原位生成的BIH作为氢原子载体的氢原子转移过程使CO_2·^-转化为甲酸。该工作首次证明了吖啶基光催化中的顺序质子-电子转移机制，解决了二氧化碳活化过程中质子和电子传递的长期挑战。

附：英文原文

Title: Atomically Engineered Acridine Derivatives Serve as Metal-Free and Self-Sensitized Catalysts for Solar-Driven CO2 to Formic Acid with High-Efficiency and Near-Perfect Selectivity

Author: Xianjun Yin, Kefan Zhang, Cui Xu, Qiang Gao, Mengyang Zhang, Xu-Bing Li, Hui-Qing Peng, Chen-Ho Tung, Li-Zhu Wu, Bin Liu

Issue&Volume: 2025-06-03

Abstract: Achieving efficient and selective light-driven CO2 conversion to formic acid is a significant scientific challenge, particularly when utilizing purely organic, metal-free, and earth-abundant element-based molecule photocatalysts. Herein, we first reported the discovery of acridine derivatives (DADN, PXZN, PTZN) as new-type, metal-free, self-sensitized molecule catalysts that enabled exceptional performance in solar-driven CO2 reduction to formic acid. Notably, the atomically engineered sulfur-containing heterocycle PTZN demonstrated unprecedented formate yield rate of 47.8 mmol g-1 h-1, and > 99% selectivity in a photocatalytic system using 1,3-dimethyl-1H-benzo[d]imidazol-3-ium (BI+) as proton and electron relay. The superior activity of PTZN was revealed to arise from its synergistic combination of strong CO2 binding affinity (-0.195 eV), prolonged charge-separated states (11 ns), and robust CO2 electronic coupling (2.51 eV). Comprehensive studies including in-situ electron spin resonance, in-situ infrared, and transient absorption spectroscopy unambiguously unveiled a direct single electron transfer process from the excited singlet-state acridine derivatives to CO2, generating CO2-. Moreover, a hydrogen atom transfer process utilizing in-situ generated BIH as a hydrogen atom carrier enabled the conversion of CO2- to formic acid. This work establishes the first demonstration of a sequential proton-electron transfer mechanism in acridine-based photocatalysis, resolving long-standing challenges in proton and electron delivery during CO2 activation.

DOI: 10.1002/anie.202508620

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202508620