Ding Hui, Wang Zheng, Ma Ziqing, Li Qianqi, Xiao Lulan, Wang Wensheng, Liu Dezhi, Wei Jishi, Zhang Bo
College of Chemical Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, P. R. China.
College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang, 110034, P. R. China.
Adv Mater. 2025 Jul;37(27):e2418722. doi: 10.1002/adma.202418722. Epub 2025 Apr 14.
Achieving full-color time-dependent tunable phosphorescence (TDTP) in pure organic materials remains a significant challenge due to the nonradiative transition and modulation puzzle of triplet states. Herein, full-color TDTP has been realized in self-protective carbonized polymer dots (CPDs) under ambient conditions using a self-doping strategy. These CPDs are generated with dual emission centers of the high-energy N-related triplet state and the low-energy surface oxide triplet state, which are responsible for the slow-decaying blue afterglow (453 nm) and the fast-decaying green to red afterglow (513-609 nm), respectively. These luminescent centers can be activated simultaneously upon CPD aggregation due to the generated rigid networks by intra/intermolecular hydrogen-band interactions. The detailed experimental characterization and theoretical calculation confirm that the red-shifted afterglow color is attributed to a gradual reduction of their energy levels with the increasing surface C═O content and aggregation degree of CPDs. Thus, these matrix-free CPDs exhibit dynamic TDTP colors over the entire visible spectrum in the solid state after turning off 365 nm UV light. Based on their unusual phosphorescent properties and excellent photostability, these CPDs have been tested for various applications such as multidimensional dynamic information encryption and anti-counterfeiting, as well as time-delayed light-emitting diodes (LEDs).
由于三重态的非辐射跃迁和调制难题，在纯有机材料中实现全色时间相关可调磷光（TDTP）仍然是一项重大挑战。在此，通过自掺杂策略在环境条件下在自保护碳化聚合物点（CPD）中实现了全色TDTP。这些CPD由高能N相关三重态和低能表面氧化物三重态的双发射中心产生，分别负责缓慢衰减的蓝色余辉（453 nm）和快速衰减的绿色到红色余辉（513 - 609 nm）。由于分子内/分子间氢键相互作用产生的刚性网络，这些发光中心在CPD聚集时可同时被激活。详细的实验表征和理论计算证实，余辉颜色的红移归因于随着表面C═O含量和CPD聚集程度的增加，其能级逐渐降低。因此，在关闭365 nm紫外光后，这些无基质CPD在固态下在整个可见光谱范围内呈现动态TDTP颜色。基于其异常的磷光特性和优异的光稳定性，这些CPD已被测试用于各种应用，如多维动态信息加密和防伪，以及延时发光二极管（LED）。
