Affiliation:
1. Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education LIFM School of Chemistry IGCME Sun Yat‐Sen University Guangzhou 510275 China
Abstract
AbstractThermally activated delayed fluorescence (TADF) behaviors in metal halide perovskite and perovskite derivatives are rarely reported due to the absence of suitable TADF molecules that can serve as the A‐site cations. Herein, a series of novel donor‐π‐acceptor type of molecules are developed by adopting substituted phosphine and phosphonium as the electron donor and acceptor linked by the polarized π‐spacer. The prepared ((diphenylphosphaneyl)phenyl)diphenylphosphonium‐X (BzDPP‐X, X = counterions: Cl−, Br−, I−, NO3−, CH3COO− etc.) salts show bright emission in the visible range with TADF characteristics due to the strong intramolecular charge transfer (ICT). Benefiting from the spatially separated highest occupied molecular orbital and lowest unoccupied molecular orbital, small singlet‐triplet energy splitting (ΔEST) is obtained, facilitating the reverse intersystem crossing process. It turns out that the emission of BzDPP‐X is dependent on the counter anions, and the counterions help to stabilize the ICT state. Intriguingly, the emission can be tuned by integrating metal‐halide units into the above phosphonium salt. Remarkably, the zinc‐based halide exhibits a higher photoluminescence quantum yield (36.2%) than the pure benzyl(2‐(diphenylphosphaneyl)phenyl)diphenylphosphonium bromide (26.9%). This work exemplifies an easy design concept and a facile synthetic method toward ionic luminescent materials.
Funder
National Natural Science Foundation of China
Subject
Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials
Cited by
2 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献