近日，吉林大学李峰团队报道了分子内氢键助力自由基型近红外有机发光二极管实现超过850 nm发射且外量子效率达5.9%。相关论文于2025年11月25日发表于《美国化学会志》。

有机开壳发射体若能实现近红外（NIR）发光，在光电子和生物成像领域具有重要应用前景，但其高效率实现面临严峻挑战，主要受限于严重的非辐射能量损失。

研究组提出了一种理性设计策略，通过整合分子内氢键和旋转限制效应，构建高效近红外发光自由基。将吡啶并嘧啶修饰的三(2,4,6-三氯苯基)甲基骨架与供电子单元结合，设计合成了两种自由基Pm-DMNA和Pm-TPA。这两种分子具有平面化的供体-受体几何构型和刚性化构象，其结构特征增强了电荷转移相互作用，同时有效抑制了振动失活路径。实验结果表明，Pm-DMNA在783 nm处的光致发光量子效率（PLQE）高达36%，并实现了外量子效率（EQE）创纪录的5.9%的有机发光二极管（OLED），且发光波长超过850 nm。该工作通过精确的构象控制，为高效开壳发射体的设计提供了一种普适性方法。

附：英文原文

Title: Intramolecular Hydrogen Bonding Enables 5.9% External Quantum Efficiency in Radical-Based Near-Infrared Organic Light-Emitting Diodes with Emission beyond 850 nm

Author: Minzhe Zhang, You-Jun Yu, Zenghui Dai, Wenzhao Wang, Houyu Zhang, Ming Zhang, Feng Li

Issue&Volume: November 25, 2025

Abstract: Organic open-shell emitters capable of near-infrared (NIR) emission are of growing interest for optoelectronic and bioimaging applications, yet achieving high efficiency remains a fundamental challenge due to severe nonradiative losses. Here, we report a rational design strategy that integrates intramolecular hydrogen bonding and rotational restriction to construct highly emissive NIR radicals. Incorporating a pyrimidine-modified tris(2,4,6-trichlorophenyl)methyl scaffold with donor units yields two radicals, Pm-DMNA and Pm-TPA, featuring planar donor–acceptor geometries and rigidified conformations. These structural features enhance charge-transfer interactions while effectively suppressing vibrational deactivation pathways. As a result, Pm-DMNA exhibits a photoluminescence quantum efficiency (PLQE) of 36% at 783nm and enables organic light-emitting diodes (OLEDs) with a record-high external quantum efficiency (EQE) of 5.9% beyond 850nm. This work illustrates a generalizable approach for engineering efficient open-shell emitters through precise conformational control.

DOI: 10.1021/jacs.5c15749

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c15749