Light-induced enhancement of exciton transport in organic molecular crystal
有机分子晶体中激子输运的光诱导增强
有機分子結晶中の励起子輸送の光誘起増強
유기 분자 결정 중 격자 수송의 광 유도 강화
Mejora inducida por la luz del transporte de radicales en cristales moleculares orgánicos
Augmentation photoinduite du transport des excitons dans les cristaux de molécules organiques
усиление фотоиндукции переноса экситонов в органических молекулярных кристаллах
Xiao-Ze Li ¹, Shuting Dai ², Hong-Hua Fang ¹, Yiwen Ren ³, Yong Yuan ¹, Jiawen Liu ², Chenchen Zhang ², Pu Wang ⁴ ⁵, Fangxu Yang ³, Wenjing Tian ², Bin Xu ², Hong-Bo Sun ¹
¹ State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, China
中国 北京 清华大学精密仪器系 精密测试技术及仪器国家重点实验室
² State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012 China
中国 长春 吉林大学化学学院 超分子结构与材料全国重点实验室
³ Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
中国 天津 天津大学理学院天津市分子光电科学重点实验室 化学化工协同创新中心
⁴ Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
中国 北京 北京分子科学国家实验室 中国科学院化学研究所有机固体重点实验室
⁵ School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
中国 北京 中国科学院大学化学科学学院
Efficient exciton transport over long distances is crucial for organic optoelectronics. Despite efforts to improve the transport properties of organic semiconductors, the limited exciton diffusion remains a significant obstacle for light-harvesting applications. In this study, we observe phenomena where exciton transport is significantly enhanced by light irradiation in the organic molecular crystal of 2,2'-(2,5-bis(2,2-diphenylvinyl)-1,4-phenylene) dinaphthalene (BDVPN).
The exciton transport in this material is improved, as evidenced by the increased diffusion coefficient from 10⁻³ cm²·s⁻¹ to over 1 cm²·s⁻¹ and a prolonged diffusion length from less than 50 nm to nearly 700 nm characterized by time-resolved photoluminescence microscopy (TPLM). Additionally, we confirmed the enhancement of charge transport capability under irradiation as additional evidence of improved transport properties of the material.
These intriguing phenomena may be associated with the material's twisted molecular conformation and rotatable single bonds, which facilitate light-induced structural alterations conducive to efficient transport properties. Our work provides a novel insight into developing organic semiconductors with efficient exciton transport.
