title: ortho-Heterofluorene perylenediimides: synthesis, photophysical, and exciton dynamic properties.
abstract: Previous studies suggest the perylenediimide (PDI) triplet excited state (T1) have been accessible only through bimolecular sensitization, the internal heavy-atom effect or a sophisticated cascade of nonradiative processes. Here, we designed heavy-atom-free PDIs to prompt the Tn← S1intersystem crossing (ISC) by introducing electron donating heterofluorene groups at the head positions of the electron-deficient PDI core. We obtained relatively high ISC efficiency up to 92% yield. Furthermore, promptly generated PDI triplets can sensitize the molecular oxygen quantitatively to yield1O2, with singlet oxygen generation efficiencies (ΦΔ) near to unity. These results further suggest that the ISC process of PDIs can be enhanced through the intramolecular charge transfer (ICT) interaction, providing guidelines for developing triplet-generating PDIs and related rylene diimides for optoelectronic applications.
authors.affiliation: Graduate University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. yswu@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Zhenyi
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Graduate University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. yswu@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Yi-Shi
authors.initials: YS
authors.lastname: Wu
authors.affiliation: Graduate University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. yswu@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Chen
authors.affiliation: Graduate University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. yswu@iccas.ac.cn hongbing.fu@iccas.ac.cn.
authors.forename: Chunlin
authors.initials: C
authors.lastname: Sun
authors.affiliation: Graduate University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. yswu@iccas.ac.cn hongbing.fu@iccas.ac.cn and Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, People's Republic of China and Department of Chemistry, Capital Normal University, Beijing 100048, People's Republic of China.
authors.forename: Hongbing
authors.identifier: http://orcid.org/0000-0003-4528-189X
authors.initials: H
authors.lastname: Fu