Effect of CdSe/ZnS quantum dots on color purity and electrical properties of polyfluorene based hybrid light emitting diode

•Blue color light emitting diode based on polyfluorene-CdSe/ZnS quantum dot blend is reported.•The color purity of blue light is enhanced by doping 25 wt.% of CdSe/ZnS quantum dots.•The electrical properties of the device are also enhanced.•Results are compared with 1-D photonic crystals fabricated on OLEDs.

We report enhanced color purity of hybrid organic-inorganic light emitting diode based on polyfluorene-CdSe/ZnS quanum dot (QD) blend as emissive layer. Effect on structural, optical and electrical properties of different doping concentration (0–100 wt.%) of QD in polyfluorene (PFO) was studied. Photoluminescence and electroluminescence spectra confirm the β-formation of PFO by incorporation of CdSe/ZnS QD. Photoluminescence (PL) of blend film was also compared with another method based on one dimensional photonic band gap (1D-PBG) structure that has been used for color purity. In both the cases, that is, QD doped device and 1D-PBG based structures the narrowing of PL spectra was observed. But the fabrication of QD-doped device for color purity is easier than fabricating 1D-PBG structure using multilayer dielectric coating. The present study might find application for QD based color displays, where color purity is an important requirement.

Graphical abstractEnhanced color purity of hybrid organic-inorganic light emitting diode based on polyfluorene-CdSe/ZnS quanum dot (QD) blend as emissive layer is reported. Effect on structural, optical and electrical properties of different doping concentration (0–100 wt.%) of QD in polyfluorene (PFO) was studied. It was found that the 25% QD doped PFO device showed the high color purity (Figure 1(a)) and luminance (Figure (b)).Figure optionsDownload full-size imageDownload as PowerPoint slide