Visualizing Triplet Energy Transfer in Organic Near-Infrared Phosphorescent Host-Guest Materials

被引：3

作者：

Deng, Zihao ^{[1
,2
]}

Kong, Fan-Cheng ^{[3
]}

Deng, Ziqi ^{[4
]}

Zhou, Jiaming ^{[3
]}

Yang, Shengyi ^{[1
,2
]}

He, Shan ^{[1
,2
]}

Zhang, Jianyu ^{[1
,2
]}

Zuo, Yunfei ^{[1
,2
]}

Wang, Jin ^{[1
,2
]}

Chen, Xinmeng ^{[1
,2
]}

Kwok, Ryan T. K. ^{[1
,2
]}

Jia, Guocheng ^{[1
,2
]}

Chow, Philip C. Y. ^{[3
]}

Phillips, David Lee ^{[4
]}

Alam, Parvej ^{[5
]}

Lam, Jacky W. Y. ^{[1
,2
]}

Tang, Ben Zhong ^{[1
,2
,6
]}

机构：

[1] Hong Kong Univ Sci & Technol, Chinese Natl Engn Res Ctr Tissue Restorat & Recons, Dept Chem, Kowloon, Clear Water Bay, Hong Kong, Peoples R China

[2] Hong Kong Univ Sci & Technol, Chinese Natl Engn Res Ctr Tissue Restorat & Recons, Hong Kong Branch, Kowloon, Clear Water Bay, Hong Kong, Peoples R China

[3] Univ Hong Kong, Dept Mech Engn, Pokfulam, Hong Kong, Peoples R China

[4] Univ Hong Kong, Dept Chem, Pokfulam, Hong Kong, Peoples R China

[5] Chinese Univ Hong Kong, Affiliated Hosp 2, Sch Med, Shenzhen CUHK Shenzhen,Sch Sci & Engn,Clin Transla, Shenzhen 518172, Guangdong, Peoples R China

[6] Chinese Univ Hong Kong, Inst Aggregate Sci & Technol, Sch Sci & Engn, Shenzhen CUHK Shenzhen, Shenzhen 518172, Guangdong, Peoples R China

来源：

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION | 2024年 / 63卷 / 51期

基金：

中国国家自然科学基金;

关键词：

near-infrared phosphors; room temperature phosphorescence; triplet exciton transition; host-guest materials; n-pi-n typed molecules; ROOM-TEMPERATURE PHOSPHORESCENCE; STATES;

D O I：

10.1002/anie.202412182

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Limited by the energy gap law, purely organic materials with efficient near-infrared room temperature phosphorescence are rare and difficult to achieve. Additionally, the exciton transition process among different emitting species in host-guest phosphorescent materials remains elusive, presenting a significant academic challenge. Herein, using a modular nonbonding orbital-pi bridge-nonbonding orbital (n-pi-n) molecular design strategy, we develop a series of heavy atom-free phosphors. Systematic modification of the pi-conjugated cores enables the construction of a library with tunable near-infrared phosphorescence from 655 to 710 nm. These phosphors exhibit excellent performance under ambient conditions when dispersed into a 4-bromobenzophenone host matrix, achieving an extended lifetime of 11.25 ms and a maximum phosphorescence efficiency of 4.2 %. Notably, by eliminating the interference from host phosphorescence, the exciton transition process in hybrid materials can be visualized under various excitation conditions. Spectroscopic analysis reveals that the improved phosphorescent performance of the guest originates from the triplet-triplet energy transfer of abundant triplet excitons generated independently by the host, rather than from enhanced intersystem crossing efficiency between the guest singlet state and the host triplet state. The findings provide in-depth insights into constructing novel near-infrared phosphors and exploring emission mechanisms of host-guest materials.

引用

页数：11