Asymmetric anthracene-based blue host materials: synthesis and electroluminescence properties of 9-(2-naphthyl)-10-arylanthracenes
作者:Kyung-Ryang Wee、Won-Sik Han、Ju-Eun Kim、Ae-Li Kim、Soonnam Kwon、Sang Ook Kang
DOI:10.1039/c0jm02877k
日期:——
A series of bulky aryl-substituted asymmetric anthracene blue host materials, 9-(2-naphthyl)-10-(3-(1-naphthyl)phenyl)anthracene, where phenyl was varied from H (5a), Me (5b), Ph (5e), and 1-Naph (5f) at the 6-position and Me (5c) at the 2-position, was synthesized by Suzuki coupling reaction between 10-(2-naphthyl)anthracene-9-boronic acid and 1-(3-iodophenyl)naphthalene derivatives. A less bulky aryl-substituted anthracene, 9-(2-naphthyl)-10-(2,5-diphenyl)phenyl)anthracene (5d), was also synthesized for comparison. All asymmetric anthracenes showed high glass transition temperatures in the range of 84–153 °C. The photophysical and electrochemical properties in solution showed that the substituent at the 10-positions of the anthracene unit did not influence the blue emission of 420 nm and HOMO–LUMO energy level (5.5–2.5 eV). However, a gradual decrease of bathochromic shift in solid state PL was observed from the increaseg of the substituent bulkiness, exhibiting 5e (18 nm) ≤ 5f (19 nm) < 5c (25 nm) ≤ 5b (26 nm) < 5a (30 nm) < 5d (41 nm), respectably. When 5a was used as a blue host material in the multilayered device structure of ITO/DNTPD/NPD/host:dopant (9%)/PyPySPyPy/LiF/Al, enhanced OLED device performance was observed, showing a luminous current efficiency of 9.9 cd A−1, power efficiency of 6.3 lm W−1 at 20 mA cm−2, deep blue color coordinates of (0.14, 0.18), and a 932 h device lifetime at L0 = 3000 cd m−2.
通过 10-(2-萘基)蒽-9(3-(1-萘基)苯基)和 10-(2-萘基)蒽-9(3-(1-萘基)苯基)之间的铃木偶联反应,合成了一系列大块芳基取代的不对称蒽蓝宿主材料,其中苯基的位置可从 H (5a)、Me (5b)、Ph (5e)、10-(2-naphthyl)anthracene-9-boronic acid 与 1-(3-碘苯基)萘衍生物之间的铃木偶联反应合成了(3-(1-萘基)苯基)蒽,其中 6 位上的苯基由 H (5a)、Me (5b)、Ph (5e) 和 1-Naph (5f),2 位上的苯基由 Me (5c)。为了进行比较,还合成了一种不太笨重的芳基取代蒽,即 9-(2-萘基)-10-(2,5-二苯基)苯基蒽(5d)。所有不对称蒽的玻璃化转变温度都很高,在 84-153 ℃ 之间。溶液中的光物理和电化学特性表明,蒽单元 10 位上的取代基并不影响 420 nm 的蓝色发射和 HOMO-LUMO 能级(5.5-2.5 eV)。然而,随着取代基体积的增大,固态 PL 的浴色偏移逐渐减小,表现为 5e (18 nm) ≤ 5f (19 nm) < 5c (25 nm) ≤ 5b (26 nm) < 5a (30 nm) < 5d (41 nm),即 5e (18 nm) ≤ 5f (19 nm) < 5c (25 nm) ≤ 5b (26 nm) < 5a (30 nm) < 5d (41 nm)。在 ITO/DNTPD/NPD/host:dopant (9%)/PyPySPyPy/LiF/Al 的多层器件结构中使用 5a 作为蓝色宿主材料时,观察到 OLED 器件性能增强,显示出 9.9 cd A-1 的发光电流效率、20 mA cm-2 时 6.3 lm W-1 的功率效率、(0.14, 0.18)的深蓝色色坐标以及 L0 = 3000 cd m-2 时 932 h 的器件寿命。