One of the biggest challenges in the field of optoelectronics is to easily identify the mechanisms involved in light-emitting materials. There are several different mechanisms of emission, and the best known are fluorescence (FL), phosphorescence (PH), thermally activated delayed fluorescence (TADF), and triplet–triplet annihilation (TTA). In this study, simple ways to diagnose these mechanisms are presented with an example. N,N-di(benzenesulfonylphenyl)-N-(N-2-aminomethylpyridine-1,8-naphthalimide)amine is synthesized as a host compound due to its high HOMO-LUMO and ionization potential (IP) values and three emitters consisting of 50 wt% Bis (1phenylisoquinoline))(acetylacetonate)iridium(III) (Ir(piq)₂(acac)), 10-(4-(4,6-Diphenyl-1,3,5-triazin-2-yl)phenyl)-9,9-dimethyl-9,10-dihydroacridine (DMAC-TRZ) and 1,1′-(2,5-Dimethyl-1,4-phenylene)dipyrene (DMPPP) were considered. Overall, the host compound, doped Ir(piq)₂(acac) and doped DMPPP follow the mechanisms of FL, the combination of FL and PH, and the combination of FL and TTA, as the photoluminescence (PL) decay life time and the PL intensity increased with decreasing temperature. However, DMAC-TRZ doped with the host compound showed the TADF mechanism, as the PL decay lifetime and the PL intensity increase simultaneously with increasing temperature. In addition, the difference between the singlet excited state (S₁) and the triplet excited state T₁ (ΔE_ST) from the PL and PH spectra at 77 K for the spin-coated DMAC-TRZ-doped host show the lowest value in between the samples at 0.02 eV, and the reverse intersystem crossing (rISC) effect is activated. Moreover, the linear slopes of the power dependence analysis of the DMPPP-doped host were calculated to be 2.04 and 0.91, indicating that there are two components (photons) for this sample which is strong evidence for the TTA mechanism. Taking into account the synthesized host compound, (Ir(piq)₂(acac):host), (DMAC-TRZ:host) and (DMPPP:host) as emitter layers, the organic light emitting diodes (OLEDs) were fabricated via solution processing, and the TADF OLED exhibited the highest efficiency among the other OLEDs.

光电子领域最大的挑战之一是轻松识别发光材料所涉及的机制。有几种不同的发射机制，最著名的是荧光 (FL)、磷光 (PH)、热激活延迟荧光 (TADF) 和三重态-三重态湮没 (TTA)。在本研究中，通过示例介绍了诊断这些机制的简单方法。N,N-二(苯磺酰基苯基)-N-(N-2-氨基甲基吡啶-1,8-萘二甲酰亚胺)胺由于其高HOMO-LUMO和电离势(IP)值以及由以下组成的三个发射器而被合成作为主体化合物50 wt% 双(1苯基异喹啉))(乙酰丙酮)铱(III) (Ir(piq) ₂ (acac)), 10-(4-(4,6-二苯基-1,3,5-三嗪-2-基)考虑了苯基）-9,9-二甲基-9,10-二氢吖啶（DMAC-TRZ）和1,1'-（2,5-二甲基-1,4-亚苯基）二芘（DMPPP）。总体而言，主体化合物掺杂的Ir(piq) ₂ (acac)和掺杂的DMPPP遵循FL、FL和PH的组合以及FL和TTA的组合的机制，因为光致发光(PL)衰减寿命和PL 强度随着温度的降低而增加。然而，掺杂主体化合物的DMAC-TRZ表现出TADF机制，随着温度的升高，PL衰变寿命和PL强度同时增加。此外，旋涂 DMAC-TRZ 掺杂主体的 77 K PL 和 PH 光谱中单重激发态 (S ₁ ) 和三重激发态 T ₁ (ΔE _ST ) 之间的差异显示出最低值样品之间的电压为 0.02 eV，反向系间窜越 (rISC) 效应被激活。此外，DMPPP 掺杂主体的功率依赖性分析的线性斜率计算为 2.04 和 0.91，表明该样品有两个分量（光子），这是 TTA 机制的有力证据。考虑到合成的主体化合物(Ir(piq) ₂ (acac):host)、(DMAC-TRZ:host)和(DMPPP:host)作为发射层，通过溶液制备有机发光二极管(OLED) TADF OLED 在其他 OLED 中表现出最高的效率。