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Updated: Jan 17, 2026
06:25
Step-by-Step Guide for Harnessing Organic Light Emitting Diodes by Solution Processed Device Fabrication of a TADF Emitter
Published on: November 7, 2025
414
Increasing Aromaticity in Selenium-Embedded Hetero Ring Enables Stable Narrowband Multi-Resonance TADF Emitter for
Jiahui Liu1,2, Jingsheng Miao1, Junjie Dong1
1Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|September 24, 2025
Summary
A new selenium-based molecule (DBSe-BN) enhances organic light-emitting diodes (OLEDs) with narrow, efficient, and stable pure-green emission, overcoming previous limitations in thermally activated delayed fluorescent (TADF) materials.
Area of Science:
- Materials Science
- Organic Electronics
- Photophysics
Background:
- High-performance organic light-emitting diodes (OLEDs) require materials with narrowband emission, high efficiency, and operational stability.
- Thermally activated delayed fluorescence (TADF) materials face challenges in simultaneously achieving these properties.
Purpose of the Study:
- To develop a novel molecular architecture for TADF materials that overcomes limitations of existing hexagonal systems.
- To achieve high-performance pure-green emission in OLEDs with enhanced efficiency and stability.
Main Methods:
- Strategic integration of selenium (Se) into a rigid pentagonal aromatic sextet (dibenzoselenophene, DBSe) within a multi-resonance (MR) framework.
- Fabrication and characterization of OLED devices using the novel DBSe-BN molecule.
Main Results:
- The developed DBSe-BN molecule exhibits a rapid reverse intersystem crossing (RISC) rate (~10^6 s^-1) and narrow emission bandwidth (21 nm).
- OLEDs based on DBSe-BN achieved a maximum external quantum efficiency (EQEmax) of 38.8% with suppressed roll-off (EQE1000 = 33.7%).
- Exceptional operational stability was demonstrated with prolonged lifetimes (LT50) of 1341 h (binary) and 5310 h (ternary) at 1000 cd/m^2.
Conclusions:
- The Se-embedded aromatic sextet strategy offers a feasible approach for high-performance MR-TADF emitters.
- This work presents a multi-dimensionally balanced OLED with improved FWHM, CIE coordinates, EQE, roll-off, and lifetime.
Keywords:
aromatic sextetdevice stabilitydibenzoselenophenemulti‐resonance fluorescent emitterpure‐green organic light‐emitting diodeMore Related Videos
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