溶剂效应对DCM发光特性的影响

Solvent Effect on DCM Photoluminescence

有机发光二极管利用有机半导体光电功能材料的电致发光效应,具有许多优异性能,是新一代有发展前途的平板显示器件及光源。有机发光材料的光电特性、光物理、光化学过程直接决定了有机发光二极管的性能。利用荧光光谱方法观察典型高效有机小分子激光染料DCM在不同溶剂中的发光特性,研究其与溶剂分子的相互作用,即溶剂效应对其发光特性的影响。结果表明DCM溶液的荧光光谱中心波长随溶剂极性增大而红移,相对发光强度基本上随溶剂极性增大。同时,还观察了不同浓度DCM溶液的发光特性,研究DCM分子间相互作用导致的浓度猝灭效应,结果表明DCM溶液浓度为10-6mol/L时,DCM溶液相对发光强度最大。

Organic light-emitting diodes （OLEDs）, which based on the electroluminescence of organic semiconductors, are promising for novel flat-panel display and lighting applications with many fascinating characteristics. OLEDs＇ performance is essentially and directly determined by the organic semiconductor materials and photo-physics/chemistry processes in the materials. This paper is mainly concerning the photoluminescence characteristic of a typical organic small molecular fluorescent dye, DCM, in different solvent by analyzing the fluorescent spectra of the solutions with different concentration. It offers a probe for interaction between the organic material molecules, i.e. “concentration quenching effect”, and the surrounding solvent molecules, i.e.“solvent effect” which impact on DCM photoluminescence characteristic. It was found that the peak emission wavelength （ A max ） of the DCM solutions took a red-shift as the solvent＇s polarity increased, along with an increase in the fluorescent intensity while the λ max varied from 569 nm for the non-polar solvent, benzene, to 627 nm for the highly polar solvent, dimethylsufoxide （DMSO）. It was also found that DCM solutions with a concentration of 10-6 mol/L exhibited the highest fluorescent intensities while DCM solutions with heavy concentration exhibited lower fluorescent intensity due to concentration quenching effect.