B,N-doped nanographenes are promising narrowband blue dopants, but slow reverse intersystem crossing limits them. Cao et al. compare three quadruple-borylated nanographenes with the same atoms but different topologies, from curved to almost planar. Greater planarity strengthens the resonance effect, delocalizes charge transfer and stiffens the molecule. The most planar emitter, QB-I, has an emission bandwidth of only 13 nm and a RISC rate of 2.7 x 10^6 s-1, and its OLED reaches 30.4% EQE at 1,000 cd m-2 with CIE (0.127, 0.078). Setfos 5.1 optical simulations estimated the outcoupling efficiency of each emitter.
Figure 5 from Cao et al. (2026), Nature Communications, reproduced under CC BY-NC-ND 4.0.
Publication details
Authors: Xiaosong Cao, Xingyu Huang, Jingsheng Miao, Yuxi Guo, Hongli Sun, Chenliang Su, Like Sun, Yanglong Liao, Zhi Chen, Cheng Zhong, Xue Zhou, Yu Gu, Hong Lin, Xialei Lv, Nengquan Li, Zhongyan Huang, Zhanxiang Chen, Tao Hua, Xiaojun Yin, Yang Zou, and Chuluo Yang
Journal: Nature Communications
Year: 2026
DOI: 10.1038/s41467-026-73679-9
PDF link: https://doi.org/10.1038/s41467-026-73679-9. The article is open access under CC BY-NC-ND 4.0.
Fluxim tools used
Setfos — version 5.1 used for OLED optical simulations based on ellipsometry data and the emitting-layer PL spectrum.
Why it matters
Shows that molecular topology, not only pi-extension, sets RISC speed and colour purity in nanographene emitters.
Setfos gave outcoupling efficiencies of 28.9%, 32.3% and 34.1% for QB-U, QB-J and QB-I, matching their increasing horizontal dipole orientation.
Moves deep-blue narrowband OLEDs closer to ultrahigh-definition display requirements.
FAQs
Which Fluxim tool was used in this paper?
Setfos 5.1 was used for optical simulations of the OLED devices.
What performance did the deep-blue OLED reach?
An EQE of 30.4% at 1,000 cd m-2 with CIE coordinates of (0.127, 0.078).
How narrow is the emission?
The most planar emitter has an emission bandwidth of 13 nm (0.07 eV).