Crystalline organic semiconductors are potentially attractive media for advanced organic solid-state light-emitting devices due to their advantageous highly oriented transition dipole moments and high mobility of charge carriers, which should in principle lead to efficient light emission; however, crystalline organic semiconductor-based organic light-emitting diodes (C-OLEDs) have until now struggled with poor device performance. Here we report a method to create high-performance C-OLEDs by using organic solid-solution thin films of deep-blue fluorescent materials. Our C-OLED exhibits a strong photon output capacity and has an external quantum efficiency of up to 6.5% with Commission Internationale de L’Eclairage (CIE) colour coordinates of around (0.15, 0.07). The driving voltage (4.0 V@1,000 cd m–2), power efficiency (3.9 lm W–1@1,000 cd m–2) and series-resistance joule-heat loss ratio (11.1%@1,000 cd m–2) outperform deep-blue amorphous OLEDs (CIEy ≤ 0.08), making it an attractive approach for next-generation OLED technologies.
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This work was funded by the National Key R&D Program of China (grant no. 2017YFA0204704 to D.H.Y). We acknowledge Jilin Yuanhe Electronic Material Company for support in preparing materials, Y. Wang for support in calculating TDM, D. Ma and D. Yang for support in measuring angle-dependent photoluminescence.
The authors declare no competing interests.
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Sun, P., Liu, D., Zhu, F. et al. An efficient solid-solution crystalline organic light-emitting diode with deep-blue emission. Nat. Photon. 17, 264–272 (2023). https://doi.org/10.1038/s41566-022-01138-0