2026/07/28 by Jun Hyeon Lee, Minlang Yang, Takuma Yasuda
Chemistry · Engineering · Materials Science · #Diode #Electroluminescence #Fluorescence #Luminescence and Fluorescent Materials #Narrowband #Organic Light-Emitting Diodes Research #Organoboron and organosilicon chemistry #Photoluminescence #Quantum #Quantum efficiency
paper · doi:10.1002/ange.6875427
published in Angewandte Chemie (Wiley)
openalex publication_date 2026/07/28 · openalex created_date 2026/07/29 · openalex updated_date 2026/07/30
ABSTRACT Multi‐resonance thermally activated delayed fluorescence (MR‐TADF) emitters enable narrowband electroluminescence with exceptional color purity in organic light‐emitting diodes (OLEDs). However, extending emission to longer wavelengths, particularly into the red region, while preserving spectral sharpness remains challenging. Here, we report a divergent one‐pot borylation strategy that transforms a single 5,11‐dihydroindolo[3,2‐ b ]carbazole platform into three structurally distinct organoboron MR‐TADF emitters spanning green to red. This approach harnesses competing mono‐ and double‐borylation pathways that coexist under the reaction conditions to generate multiple emitters in a single operation. The resulting MR‐TADF emitters ( BN‐G , BN‐Y , and BN‐R ) exhibit ultranarrow green, yellow, and red photoluminescence with full widths at half maximum below 25 nm and near‐unity quantum yields (96%–100%) in doped films. OLEDs based on these emitters achieve maximum external quantum efficiencies of up to 35.3%, with emission maxima spanning 516–601 nm. This study establishes a unified design strategy for generating multiple high‐performance MR‐TADF emitters from a single precursor, providing a versatile platform for the development of color‐tunable narrowband optoelectronic materials.