Ultrastable Supramolecular Self-Encapsulated Wide-Bandgap Conjugated Polymers for Large-Area and Flexible Electroluminescent Devices

作者:Lin, Jinyi; Liu, Bin; Yu, Mengna; Wang, Xuhua; Lin, Zongqiong; Zhang, Xinwen; Sun, Chen; Cabanillas-Gonzalez, Juan; Xie, Linghai; Liu, Feng; Ou, Changjin; Bai, Lubing; Han, Yamin; Xu, Man; Zhu, Wensai; Smith, Trevor A.; Stavrinou, Paul N.; Bradley, Donal D. C.; Huang, Wei*
来源:Advanced Materials, 2019, 31(1): 1804811.
DOI:10.1002/adma.201804811

摘要

Controlling chain behavior through smart molecular design provides the potential to develop ultrastable and efficient deep-blue light-emitting conjugated polymers (LCPs). Herein, a novel supramolecular self-encapsulation strategy is proposed to construct a robust ultrastable conjugated polydiarylfluorene (PHDPF-Cz) via precisely preventing excitons from interchain cross-transfer/coupling and contamination from external trace H2O/O-2. PHDPF-Cz consists of a mainchain backbone where the diphenyl groups localize at the 9-position as steric bulk moieties, and carbazole (Cz) units localize at the 4-position as supramolecular pi-stacked synthon with the dual functionalities of self-assembly capability and hole-transport facility. The synergistic effect of the steric bulk groups and pi-stacked carbazoles affords PHDPF-Cz as an ultrastable property, including spectral, morphological stability, and storage stability. In addition, PHDPF-Cz spin-coated gelation films also show thickness-insensitive deep-blue emission with respect to the reference polymers, which are suitable to construct solution-processed large-scale optoelectronic devices with higher reproducibility. High-quality and uniform deep-blue emission is observed in large-area solution-processed films. The electroluminescence shows high-quality deep-blue intrachain emission with a CIE (0.16, 0.12) and a very narrow full width at half-maximum of 32 nm. Finally, large-area and flexible polymer light-emitting devices with a single-molecular excitonic behavior are also fabricated. The supramolecular self-encapsulation design provides an effective strategy to construct ultrastable LCPs for optoelectronic applications.