Stereoisomer-Independent Stable Blue Emission in Axial Chiral Difluorenol

• Main Authors: Mengna Yu, Xiong Jia, Dongqing Lin, Xue Du, Dong Jin, Ying Wei, Linghai Xie, Wei Huang
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2021-09-01
• Series: Frontiers in Chemistry
• Subjects: axial chiral; deep blue; stereoisomer; difluorenol; spirobifluorene
• Online Access: https://www.frontiersin.org/articles/10.3389/fchem.2021.717892/full

Bulky conjugated molecules with high stability are the prerequisite for the overall improvement of performance in wide-bandgap semiconductors. Herein, a chiral difluorenol, 2,2′-(9,9′-spirobi[fluorene]-2,2′-diyl)bis(9-(4-(octyloxy)phenyl)-9H-fluoren-9-ol) (DOHSBF), is set as a desirable model to reveal the stereoisomeric effects of wide-bandgap molecules toward controlling photophysical behavior and improving thermal and optical stability. Three diastereomers are obtained and elucidated by NMR spectra. Interestingly, the effect of modifying the stereo-centers is not observed on optical properties in solutions, pristine films, or post-treated film states. All three diastereomers as well as the mixture exhibit excellent spectral stability without undesirable green emission. Therefore, this stereoisomer-independent blue-emitting difluorenol will be a promising candidate for next-generation wide-bandgap semiconductors that would have extensive application in organic photonics.