《Structural isomers of 9-(pyridin-2-yl)-9H-carbazole in combination with 9’H-9,3′:6′,9”-tercarbazole and their application to high efficiency solution processed green TADF OLEDs》 was written by Hwang, Jinhyo; Yoon, Jiwon; Kim, Chae Yeong; Choi, Suna; Kang, Hyunchul; Kim, Jun Yun; Yoon, Dae-Wi; Han, Chang Wook; Park, Sungnam; Cho, Min Ju; Choi, Dong Hoon. Formula: C5H3Br2N And the article was included in Dyes and Pigments in 2020. The article conveys some information:
Two host materials, CzPy2TCz and CzPy3TCz, were designed as structural isomers and synthesized to achieve high efficiency thermally activated delayed fluorescence-organic light emitting diodes (TADF-OLEDs). The design strategy involved introducing a pyridine group into the core structure as an electron-withdrawing unit and varying the substitution position of tercarbazole (TCz). To realize green TADF-OLED, the 2 host materials synthesized in this study have excellent thermal stability and high excited triplet energy (T1 = 2.95-2.98 eV). The maximum external quantum efficiency and current efficiency values for CzPy2TCz were 23.81% and 80.2 cd/A, resp. and the resp. values for CzPy3TCz were 20.27% and 70.1 cd/A, resp. Structural isomers with carbazole (Cz) and TCz units at the 2,6-position of the pyridine core effectuate better device performance. Consequently, the host materials introduced in this study play an important role in implementing high performing solution-processed green TADF-OLED. The experimental process involved the reaction of 2,5-Dibromopyridine(cas: 624-28-2Formula: C5H3Br2N)
2,5-Dibromopyridine(cas: 624-28-2) belongs to pyridine. Pyridine is a relatively complex molecule and exhibits a number of different bands in IR spectra. Among others, the bands characterizing the ν8a and ν19b modes have been found to be sensitive to the coordination or protonation of the molecule. Note that the band that is diagnostic for the PyH+ ion at about 1545 cm− 1 (ν19b mode) does not overlap with any of the other bands.Formula: C5H3Br2N