Lee JaMin, Lee Sae Won, Kim Young Sik
Department of Information Display, Hongik University, Seoul, 04066, Korea.
J Nanosci Nanotechnol. 2020 Nov 1;20(11):7187-7190. doi: 10.1166/jnn.2020.18855.
We designed novel thermally activated delayed fluorescence (TADF) materials by combining the electron donors spiro[acridine-9,9'-fluorene] (D1) and 9,9-diphenyl acridan (PAC) with the electron acceptor phenoxaphosphine (OPO) unit (2D1-OPO and 2PAC-OPO) and used those property to compare it with that of the reference material using dimethylacridan (Ac) as an electron donor (Ac-OPO) for blue organic light-emitting diodes (OLEDs). To calculate electron distribution of highest occupied molecular orbitals (HOMO), lowest occupied molecular orbital (LUMO), lowest singlet () energy and lowest triplet () excitation states, density functional theory (DFT) and time-dependent DFT calculation have been used. The calculated energy difference (Δ) between the and states of 2D1-OPO (0.125 eV) and 2PAC-OPO (0.153 eV) were as small as that of Ac-OPO (0.127 eV). The results showed that 2D1-OPO is a good candidate for blue OLED emitter because it has an emission wavelength of 441.0 nm as well as a sufficiently small Δ value and large oscillator intensity value.
我们通过将电子供体螺[吖啶-9,9'-芴]（D1）和9,9-二苯基吖啶（PAC）与电子受体苯并恶磷（OPO）单元（2D1-OPO和2PAC-OPO）相结合，设计了新型热激活延迟荧光（TADF）材料，并利用这些特性将其与以二甲基吖啶（Ac）作为电子供体的参考材料（Ac-OPO）用于蓝色有机发光二极管（OLED）的性能进行比较。为了计算最高占据分子轨道（HOMO）、最低未占据分子轨道（LUMO）、最低单重态（）能量和最低三重态（）激发态的电子分布，使用了密度泛函理论（DFT）和含时DFT计算。2D1-OPO（0.125 eV）和2PAC-OPO（0.153 eV）的和态之间计算出的能量差（Δ）与Ac-OPO（0.127 eV）的一样小。结果表明，2D1-OPO是蓝色OLED发光体的良好候选材料，因为它的发射波长为441.0 nm，并且具有足够小的Δ值和大的振子强度值。
