具有热激活延迟荧光 (TADF)特性的发光材料在有机发光二极管应用领域需求量巨大。采用经典的Suzuki偶连反应合成了一种单重态-三重态能级差极小 (0.03eV)的新型桥连结构分子。通过荧光寿命随着温度的升高出现寿命延长的现象,证明了新型桥连结构分子具有明显的TADF性能;通过理论计算解释了桥连结构分子具有TADF特性的原因,并提出了电子跃迁的内在相关机理。热重分析表明合成的新型桥连结构分子热稳定性良好。
Luminescent materials exhibiting thermally activated delayed fluorescence properties are eagerly required for organic light-emitting diodes.A novel bridged structure molecule with extremely small ΔEST (0.03eV) was synthesized.Furthermore,its fluorescence lifetime was prolonged with the increase of temperature,which proved its obviously TADF phenomenon.And the reason was explained by theoretical calculation and the intrinsic mechanism of electron transition was also proposed.Thermogravimetric analysis showed its good thermal stability in high temperature,too.
[1] Endo B K,Ogasawara M,Takahashi A,et al.Thermally activated delayed fluorescence from Sn4+-porphyrin complexes and their application to organic light-emitting diodes-a novel mechanism for electroluminescence[J].Advanced Materials,2009,21 (47):4802-4806.
[2] Uoyama H,Goushi K,Shizu K,et al.Highly efficient organic light-emitting diodes from delayed fluorescence[J].Nature Letter,2012,492 (7428):234-238.
[3] Zhang Q S,Li J,Shizu K,et al.Design of efficient thermally activated delayed fluorescence materials for pure blue organic light emitting diodes[J].Jounal of the American Chemical Society,2012,134 (36):14706-14709.
[4] Tao Y,Yuan K,Chen T,et al.Thermally activated delayed fluorescence materials towards the breakthrough of organoelectronics[J].Advanced Materials,2014,26 (47):7931-7958.
[5] Yang Z Y,Mao Z,Xie Z L,et al.Recent advances in organic thermally activated delayed fluorescence materials[J].Chemical Society Reviews,2017,46 (3):915-1016.
[6] Park I S,Lee S Y,Adachi C,et al.Full-color delayed fluorescence materials based on wedge-shaped phthalonitriles and dicyanopyrazines:systematic design,tunable photophysical properties,and OLED performance[J].Advanced Functional Materials,2016,26 (11):1813-1821.
[7] Shiu Y J,Chen Y T,Lee W K,et al.Efficient thermally activated delayed fluorescence of functional phenylpyridinato boron complexes and high performance organic light-emitting diodes[J].Journal of Materials Chemistry C,2017,5 (6):1452-1462.
[8] Li Y F,Xie G H,Gong S L,et al.Dendronized delayed fluorescence emitters for non-doped,solution-processed organic lightemitting diodes with high efficiency and low efficiency roll-off simultaneously:two parallel emissive channels[J].Chemical Science,2016,7 (8):5441-5447.
[9] Tanaka H,Shizu K,Nakanotanie H,et al.Twisted intramolecular charge transfer state for long-wavelength thermally activated delayed fluorescence[J].Chemistry of Materials,2013,25 (18):3766-3771.
[10] Zhang Q S,Li B,Huang S P,et al.Efficient blue organic light-emitting diodes employing thermally activated delayed fluorescence[J].Nature Photonics,2014,8 (4):326-332.
[11] Zhang Q S,Tsang D,Kuwabara H,et al.Nearly 100% internal quantum efficiency in undoped electroluminescent devices employing pure organic emitters[J].Advanced Materials,2015,27 (12):2096-2100.
[12] Li J,Zhang R,Wang Z Q,et al.Zig-zag acridine/sulfone derivative with aggregation induced emission and enhanced thermally activated delayed fluorescence in amorphous phase for highly effcient nondoped blue organic light-emitting diodes[J].Advanced Optical Materials,2018,6 (6):1701256-1701262.
[13] Li C,Du X Y,Zhou Y,et al.A simple and broadly applicable synthesis of fluorene-coupled D-δ-A type molecules:towards high-triplet-energy bipolar hosts for efficient blue thermally-activated delayed fluorescence[J].Journal of Materials Chemistry C,2018,6 (26):6949-6957.
基金资助
国家自然科学基金(51603088);江苏省自然科学基金(BK20150154)
PDF
(1602KB)
