【Academic writing Sharing 20180313】
Diboron compound-based organic light-emitting diodes with high efficiency and reduced efficiencyroll-off
Article excerpt is from:Tien-Lin Wu, Min-Jie Huang, Chih-Chun Lin, Pei-Yun Huang, Tsu-Yu Chou,Ren-Wu Chen-Cheng, Hao-Wu Lin, Rai-Shung Liu and Chien-Hong Cheng
Nature Photonics (2018)
Here, we report the design and synthesis of two diboron-based molecules, CzDBA and tBuCzDBA, which show excellent TADF properties and yield efficient OLEDs with very low efficiency roll-off. These donor–acceptor–donor (D–A–D) type and rodlike compounds concurrently generate TADF with a photoluminescence quantum yield of ~100% and an 84% horizontal dipole ratio in the thin film. A green OLED based on CzDBA exhibits a high external quantum efficiency of 37.8 ± 0.6%, a current efficiency of 139.6 ± 2.8 cd A−1 and a power efficiency of 121.6 ± 3.1 lm W−1 with an efficiency roll-off of only 0.3% at 1,000 cd m−2. The device has a peak emission wavelength of 528 nm and colour coordinates of the Commission International de l’Eclairage (CIE) of (0.31, 0.61), making it attractive for colour-display applications.