Day: February 22, 2023

Role of Guest Materials in the Lower Stability of Solution-Coated versus Vacuum-Deposited Phosphorescent OLEDs was written by Samaeifar, Fatemeh;Aziz, Hany. And the article was included in ACS Applied Materials & Interfaces in 2022.Reference of 105598-27-4 This article mentions the following:

Utilizing different phosphorescent materials as emitter guests, this work investigates the root causes of the lower electroluminescence (EL) stability of solution-coated (SOL) organic light-emitting devices (OLEDs) relative to their vacuum-deposited (VAC) counterparts. The results show that emitter guest mols. aggregate under elec. stress, leading to the emergence of new longer-wavelength bands in the EL spectra of the devices over time. However, the intensity of these aggregation emission bands is much stronger in the case of SOL host:guest systems than that of their VAC counterparts, indicating that guest aggregation occurs much faster in the former. The results reveal that the phenomenon arises from differences in the initial morphologies and are likely associated with the use of solvents in the solution-coating process. Moreover, although excitons can drive this aggregation in the case of SOL emissive layer (EML) devices, the coexistence of excitons and polarons accelerates this phenomenon significantly. The results uncover one of the main causes of the lower stability of OLEDs made by solution coating and reveal the importance of adopting new mol. designs that make them less susceptible to aggregation for the development of SOL OLEDs with high performance. In the experiment, the researchers used many compounds, for example, Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4Reference of 105598-27-4).

Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4) belongs to quinoxaline derivatives. Quinoxalines are important class of heterocyclic compounds, associated with wider pharmacological applications. Modifying quinoxaline structure it is possible to obtain a wide variety of biomedical applications, namely antimicrobial activities and chronic and metabolic diseases treatment.Reference of 105598-27-4

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

High-performance non-doped near ultraviolet OLEDs with the EQE ∼ 6% and CIEy ∼ 0.03 from high-lying reverse intersystem crossing was written by Peng, Ling;Lv, Jichen;Xiao, Shu;Huo, Yumiao;Liu, Yuchao;Ma, Dongge;Ying, Shian;Yan, Shouke. And the article was included in Chemical Engineering Journal (Amsterdam, Netherlands) in 2022.Synthetic Route of C18N12 This article mentions the following:

Developing high-performance organic fluorophors with short-wavelength emission is both significant and challenging subject in the application of organic light-emitting diodes (OLEDs). A coupling hardness with distortion design concept is proposed to construct an efficient near UV (NUV) fluorophor mP2MPC with 1,4-dimethyl-2,5-diphenylbenzene as a rotatable bridge via the meta-positions linking rigid and bulky phenanthroimidazole and carbazole groups. The nondoped OLED with it as emitter not only exhibits an emission peak at 395 nm with the Commission Internationale de l’ećlairage coordinates of (0.163, 0.028), but also realizes a high forward-viewing external quantum efficiency of 6.09% due to the high-lying reverse intersystem crossing. The value still keeps ≤5.56% at 1000 cd m^-2, showing a small efficiency roll-off. This is 1 of the highest efficiencies among the nondoped devices with the electroluminescence peak <400 nm. The green and red phosphorescent OLEDs with mP2MPC as host can also show excellent electroluminescence performance with the forward-viewing external quantum efficiencies over 21.5%, illustrating that mP2MPC should be a prospective material for OLEDs. In the experiment, the researchers used many compounds, for example, Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4Synthetic Route of C18N12).

Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4) belongs to quinoxaline derivatives. Condensed heterocycles of quinoxalines have become attractive targets in synthetic and medicinal chemistry due to their significant biological activities. Modifying quinoxaline structure it is possible to obtain a wide variety of biomedical applications, namely antimicrobial activities and chronic and metabolic diseases treatment.Synthetic Route of C18N12

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider