(t-bt)2Ir(acac)新型磷光染料的光谱特性及电致发光性能研究

对不同浓度的新型黄色铱配合物磷光染料bis[2-(4-tertbutylphenyl)benzothiazolato-N,C2']iridium (acetylacetonate)[(t-bt)2Ir(acac)]溶液和薄膜状态下的光致发光光谱(Photoluminescence,PL)和紫外-可见吸收(UV-Vis absorption)光谱进行了表征.结果表明,溶液浓度为3×10-4mol·L-1时的PL发光最强,浓度猝灭效应使得高浓度溶液的PL强度降低.薄膜的PL和吸收光谱相对溶液的光谱都发生了红移,这是由于固态时分子间距小、相互作用大,分子表现为聚集态的结果.基于光谱特性,制备了(t-bt)2Ir(acac)超薄层结构的电致发光器件,在13.2 V的偏置电压下,器件的发光亮度达到18 367 cd·m-2.

Electroluminescent performance and spectral characteristics of a novel (t-bt)2Ir(acac) phosphorescent iridium complex

The photoluminescence (PL) spectra and UV-Visible absorption spectra of a novel yellow phosphor dye of bis[2-(4-tert-butylphenyl)benzothiazolato-N,C2'] iridium (acetylacetonate) denoted as (t-bt)2Ir(acac) were systematically investigated, which were measured in solution and film states with various concentrations. The results showed that the highest PL intensity was achieved when the solution concentration was 3 x 10(-4) mol L(-1), and it decreased dramatically when the concentration kept on increasing because of concentration quenching of the phosphor dye. A red shift for PL spectra and UV-Vis absorption spectra of films compared to those of solutions were found, which is due to the shorter distance, aggregation effect, and stronger interaction of dye molecules in solid state. Based on the spectrum characterization, organic light-emitting diode was fabricated with an ultrathin structure based on this phosphor dye, which showed a high luminescence of 18 367 cd m(-2) at a bias of 13.2 V.