Abatti Priscila Pazini, Decarli Nícolas Oliveira, Gogoc Szymon, Data Przemyslaw, Bechtold Ivan H, Westphal Eduard, Gallardo Hugo
Department of Chemistry, Federal University of Santa Catarina, Campus Universitário Reitor João David Ferreira Lima CP 476, CEP, 88040-900, Trindade, Florianópolis/SC, Brazil.
Faculty of Chemistry, Silesian University of Technology, Księdza Marcina Strzody 9, 44-100, Gliwice, Poland.
Chempluschem. 2023 Nov;88(11):e202300539. doi: 10.1002/cplu.202300539. Epub 2023 Oct 17.
Three tetraaryl-1,4-dihydropyrrolo[3,2-b]pyrrole derivatives containing different number of long alkoxy chains (2, 4 and 6) were synthesized, characterized and applied in Organic Light Emitting Diodes (OLEDs). The compounds showed good emission properties with Photoluminescence Quantum Yields (PLQYs) higher than 80 % in solution and 50 % in solid state (thin film). The solvatochromism results revealed a pronounced vibronic emission in methylcyclohexane and toluene, characterized by two distinct sharp emission peaks and a small redshift in the following order: methylcyclohexane>toluene>dichloromethane>tetrahydrofuran>acetonitrile. Also, the compounds formed aggregates with redshifted emission, which can be attributed to excimer formation. This phenomenon was observed in solutions containing 90 % water and with the concentration variation in methylcyclohexane (MCH). Compounds with a greater number of peripheral chains showed the capacity to keep hexagonal columnar organization in films after fast cooling from liquid state. OLEDs fabricated with these compounds showed turn-on voltages lower than 4.0 V, with luminance higher than 1400 cd m , electroluminescence spectra with Full Width at Half Maximum lower than 70 nm and maximum External Quantum Efficiency between 7.2 % and 4.3 %. Overall, this shows that the 1,4-dihydropyrrolo[3,2-b]pyrrole moiety is promising for applications where luminescence is paramount, as in organic light-emitting devices.
合成了三种含有不同数量长链烷氧基（2、4和6）的四芳基-1,4-二氢吡咯并[3,2-b]吡咯衍生物，对其进行了表征并应用于有机发光二极管（OLED）。这些化合物表现出良好的发光性能，在溶液中的光致发光量子产率（PLQY）高于80%，在固态（薄膜）中高于50%。溶剂化显色结果表明，在甲基环己烷和甲苯中存在明显的振动发射，其特征是有两个明显的尖锐发射峰，且红移较小，顺序如下：甲基环己烷>甲苯>二氯甲烷>四氢呋喃>乙腈。此外，这些化合物形成了发射红移的聚集体，这可归因于激基缔合物的形成。在含有90%水的溶液以及甲基环己烷（MCH）浓度变化的情况下观察到了这种现象。具有更多外围链的化合物在从液态快速冷却后，能够在薄膜中保持六方柱状结构。用这些化合物制备的OLED的开启电压低于4.0 V，亮度高于1400 cd m ，半高宽低于70 nm的电致发光光谱，最大外量子效率在7.2%至4.3%之间。总体而言，这表明1,4-二氢吡咯并[3,2-b]吡咯部分在发光至关重要的应用中具有潜力，如在有机发光器件中。
