Epitomized by 4CzIPN, donor-acceptor (D-A) thermally activated delayed fluorescence (TADF) compounds based on the carbazoyl dicyanobenzene have now become widely used, as they are sustainable photocatalyst alternatives to organometallic complexes owing to their similar optoelectronic properties compared with many of the iridium-based photocatalysts. Multiresonant TADF (MR-TADF) compounds offer distinct advantages over D-A TADF compounds, as they have more intense low-energy absorption bands, offering faster reaction kinetics, and are less sensitive to the polarity of the environment, mitigating undesired energy loss that typically accompanies the charge transfer (CT) excited states of the photocatalysts. Here, we report the assessment of strongly photoreducing boron- and nitrogen-doped MR-TADF compounds DABNA-1, tDABNA, CzBN, and DtBuCzB across a range of benchmark photochemical reactions. The structural differences between the members of this library of photocatalysts enable modulation of their ground- and excited-state redox potentials. These photocatalysts performed competitively compared to the literature-known 4CzIPN, Ph-PTZ, and fac-Ir(ppy)₃.

以4CzIPN为代表的基于咔唑基二氰基苯的供体-受体 (DA) 热激活延迟荧光 (TADF) 化合物现已得到广泛使用，因为它们与许多铱具有相似的光电特性，是有机金属配合物的可持续光催化剂替代品基光催化剂。多共振 TADF (MR-TADF) 化合物比 DA TADF 化合物具有明显的优势，因为它们具有更强的低能量吸收带，提供更快的反应动力学，并且对环境极性不太敏感，从而减轻通常伴随的不需要的能量损失光催化剂的电荷转移（CT）激发态。在这里，我们报告了对强光还原硼和氮掺杂 MR-TADF 化合物DABNA-1 、 t DABNA 、 CzBN和DtBuCzB在一系列基准光化学反应中的评估。该光催化剂库成员之间的结构差异使得能够调节它们的基态和激发态氧化还原电位。与文献中已知的4CzIPN 、 Ph-PTZ和fac- Ir(ppy) ₃相比，这些光催化剂的性能具有竞争力。