郑州大学欧阳钢锋团队报道了稳定有机染料的敏化高效、无贵金属、全水CO₂光还原。相关研究成果于2024年6月18日发表在国际顶尖学术期刊《美国化学会杂志》。

高效、选择性和耐用的CO₂光还原系统的开发在全水溶液中是一个长期的挑战，因为存在稀缺的CO₂和与H₂释放的激烈竞争，当不使用贵金属时，H₂释放更具挑战性。

该文中，研究人员提出了在供体-受体型有机染料上，简单修饰四个膦酸基团以获得水溶性光敏剂（4P-DPAIPN），该光敏剂继承了其原型的优异光物理和光氧化还原性能，在水溶液中表现出长寿命的延迟荧光（>10μs）。将4P-DPAIPN与阳离子钴卟啉催化剂相结合，在全水溶液的先前系统中，CO₂到CO的光转换在450 nm处实现了创纪录的9.4-17.4%的表观量子产率（最大13%）。

这种不含贵金属的系统还可以实现82–93%的显著选择性和2700的CO生产周转数，在平行条件下优于基准钌光敏剂和商业有机染料。4P-DPAIPN的这种高性能可以在真实的阳光下很好地保持。更令人印象深刻的是，在长期光催化过程中没有检测到4P-DPAIPN的显著分解。最后，提出了光诱导电子转移的途径。

附：英文原文

Title: Highly Efficient, Noble-Metal-Free, Fully Aqueous CO2 Photoreduction Sensitized by a Robust Organic Dye

Author: Fan Ma, Zhi-Mei Luo, Jia-Wei Wang, Gangfeng Ouyang

Issue&Volume: June 18, 2024

Abstract: The development of efficient, selective, and durable CO2 photoreduction systems presents a long-standing challenge in full aqueous solutions owing to the presence of scarce CO2 and the fierce competition against H2 evolution, which is even more challenging when noble metals are not utilized. Herein, we present the facile decorations of four phosphonic acid groups on a donor–acceptor-type organic dye to obtain a water-soluble photosensitizer (4P-DPAIPN), which succeeds the excellent photophysical and photoredox properties of its prototype, exhibiting long-lived delayed fluorescence (>10 μs) in aqueous solutions. Combining 4P-DPAIPN with a cationic cobalt porphyrin catalyst has accomplished record-high apparent quantum yields of 9.4–17.4% at 450 nm for CO2-to-CO photoconversion among the precedented systems (maximum 13%) in fully aqueous solutions. Remarkable selectivity of 82–93% and turnover number of 2700 for CO production can also be achieved with this noble-metal-free system, outperforming a benchmarking ruthenium photosensitizer and a commercial organic dye under parallel conditions. Such high performances of 4P-DPAIPN can be well maintained under real sunlight. More impressively, no significant decomposition of 4P-DPAIPN was detected during the long-term photocatalysis. Eventually, the photoinduced electron transfer pathways were proposed.

DOI: 10.1021/jacs.4c03128

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c03128