Multi-Stimuli Responsive and Multicolor Adjustable Pure Organic Room Temperature Fluorescence-Phosphorescent Dual-Emission Materials
Multi-Stimuli Responsive and Multicolor Adjustable Pure Organic Room Temperature Fluorescence-Phosphorescent Dual-Emission Materials
复制标题
多刺激响应、多色可调纯有机室温荧光-磷光双发射材料
DOI：
10.1002/adfm.202101312
复制
发表时间：
2021-04-10
影响因子：
19
通讯作者：
Cao, Qiu-E
中科院分区：
文献类型：
--
作者：
Bi, Xingqi;Shi, Yonggang;Cao, Qiu-E
一个简单的溴和氰取代基位置异构的9-苯基-9H-咔唑（PhCz）给体-受体体系（即p-NN-Br和m-NN-Br）显示出超长的有机磷光，并具有独特的荧光和磷光双重发光性质。发现这些分子对包括温度（T）、激发光强度（I）和压力（P）的多种外部刺激显示出不同的响应，并且显示出可调谐的行为（包括白色光，国际照明委员会（CIE）= 0.33，0.34）。通过对p-NN-Br和m-NN-Br的电子物理光谱、扫描电镜（SEM）成像和X射线分析，结合理论计算，系统地证明了它们的单重态和三重态激子之间独特的激发触发比例.结果表明，同时引入卤素（Br）和拟卤素（CN）的PhCz骨架可以改善分子间的相互作用和热稳定性。单晶分析表明，有更多类型的二聚体和J-聚集体，从而稳定的激发三重态。而且这些异构体具有“潜伏”指纹识别和抗背景干扰性能，有望为指纹识别提供新的方法。总而言之，这一策略为开发多刺激响应、荧光调节和在室温下具有长寿命发射的智能发光材料的多功能平台铺平了道路。
A simple bromine and cyanogen substituents positional isomeric 9-phenyl-9H-carbazole (PhCz) donor-acceptor system (namely p-NN-Br and m-NN-Br) displays ultralong organic phosphorescence, and exhibits unique dual emission properties (fluorescence and phosphorescence). These molecules are found to display distinct responses toward multiple external stimuli including temperature (T), excitation light intensity (I) and pressure (P), and show multicolor tunable behaviors (including the white light, the Commission Internationale d'Eclairage (CIE) = 0.33, 0.34). The unique stimuli-triggered proportion between singlet and triplet excitons for p-NN-Br and m-NN-Br is demonstrated systematically by investigating the photophysical spectrum, scanning electron microscope (SEM) imaging and X-ray analysis, coupled with theoretical calculations. They reveal that the simultaneous introduction of halogens (Br) and pseudohalogens (CN) to the PhCz skeleton can improve the intermolecular interaction and thermal stability. Single crystal analysis shows that there are many more types of dimers and J-aggregates, thereby stabilizing the excitation of triplet states. Moreover, these isomers have "latent" fingerprint recognition and anti-background interference performance, which is expected to provide a new method for fingerprint identification. All in all, this strategy paves the way to a multifunctional platform for the development of multi-stimuli responsive, multicolor regulation and smart luminescent materials with long-lived emission at room temperature.