【摘要】 研制高效载流子传输材料是提高有机电致发光器件性能的关键.采用对酯对二酰氯(5)与含不同链长烷氧取代基的苯甲酰肼(2)缩合制备了一系列腰接羧基1,3,4-噁二唑衍生物,即1,4-二[5-(4-烷氧基苯)-1,3,4-噁二唑基]-2,5-二羧基苯(7;烷氧基=OCnH2n+1;n=8,12,16),并采用UV-vis吸收和荧光光谱对合成物进行了表征.结果表明:7的分子结构中羧基的横向引入,对化合物的光物理性质和能带结构产生较大影响.这些噁二唑化合物的LUMO及HOMO值分别介于-3.62与-3.58eV之间及-6.94与-6.90eV之间,说明它们可能具有良好的电子传输性.更多还原

【Abstract】 Preparation of high-efficiency carrier transport material is a key to fabricate more efficient and high performance organic and polymeric light-emitting devices. A series of rod-coil 1,3,4-oxadiazole deriva-tives with lateral carboxyls, 1,4-bis[5-(4-alkoxyphenyl)-1,3,4-oxadiazol-2-yl]-2,5-di(carboxy)benzenes (7; alkoxy=OCnH2n+1; n=8, 12 and 16) were synthesized by condensation of terephthaloyl chloride (5) with benzohydrazides containing alkoxy chains with different lengths (2). The results show that introduction of two carboxyls whose electron-accepting ability is stronger reduces the electron density of the conjugated segment of 7, and thus leads to the absorption maximum bathochromic-shift compared to 8 (without car-boxyl group). Calculation on the representative compound by the Dmol3 package of MS Modeling 3.0 re-vealed that the decrease of energy levels in 7 was due to the change of the frontier molecular orbital distribu-tion in the central benzene ring because of introduction of two carboxyls. The HOMO and LUMO energy levels of the compounds studied are in the range of -3.62～-3.58 eV and -6.94～-6.90 eV, which showed that they functioned well as electron-transporting materials.更多还原