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 photolumine-(scence) 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(λ

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.