Guo Yan, Zhou Qixin, Wang Li, Deng Ziqi, Phillips David Lee, Tang Chuyang Y, Zhu Yongfa
Department of Civil Engineering, The University of Hong Kong, Hong Kong, China.
Department of Chemistry, Tsinghua University, Beijing, China.
Nat Commun. 2025 Jul 8;16(1):6297. doi: 10.1038/s41467-025-61452-3.
Organic photocatalysts with porphyrin conjugated chromophore core are promising for artificial hydrogen peroxide (HO) photosynthesis, but the lack of bottom-up paradigm for oxygen (O) adsorption sites hinders their activity. Here, we introduce imidazole groups as π-electron sites with charge-complementarity to the O molecules, enhancing O binding via sub-atomically mirrored electrostatic cooperative π-π dispersion forces. In situ spectroscopy and theory reveal that the ~2 Å linear δ-δ-δ domain of the imidazole substituent exhibits 2.8-folds stronger O adsorption than neutral π-electron substituents, accompanied by the generation of energetically peroxide intermediates. Consequently, imidazole-substituted porphyrin photocatalysts achieve a solar-to-chemical conversion efficiency of 1.85% using only HO and O. In scalable membranes with photocatalysts, enabling daily photosynthetic production of 80 L m of Fenton-applicable HO solution. This work offers a strategy to modulate the electrostatic distribution of oxygen photoreduction sites, providing insights into overcoming gas activation rate-limiting steps in photocatalytic processes.
具有卟啉共轭发色团核心的有机光催化剂在人工过氧化氢（HO）光合作用方面具有潜力，但缺乏用于氧（O）吸附位点的自下而上范式阻碍了它们的活性。在此，我们引入咪唑基团作为与O分子具有电荷互补性的π电子位点，通过亚原子镜像静电协同π-π色散力增强O的结合。原位光谱和理论表明，咪唑取代基的~2Å线性δ-δ-δ域对O的吸附比中性π电子取代基强2.8倍，同时伴随着高能过氧化物中间体的生成。因此，咪唑取代的卟啉光催化剂仅使用HO和O就能实现1.85%的太阳能到化学能的转换效率。在含有光催化剂的可扩展膜中，能够每天光合生产80 L m的适用于芬顿反应的HO溶液。这项工作提供了一种调节氧光还原位点静电分布的策略，为克服光催化过程中气体活化速率限制步骤提供了见解。
