Improvement of color purity and electrical characteristics by co-doping method for flexible red-light organic light emitting devices

This work demonstrates the improvement of the color purity and electrical characteristics for flexible red-light organic light emitting devices (FROLEDs). The devices were prepared by vacuum deposition on ITO-plastic substrates. These guest materials of DCJTB and Rubrene were doped into the host material of Alq3, resulting in an emitting layer. Experimental results reveal that the properties in the above case are better than those of the emitting layer with a single DCJTB guest material, reaching the commercial red-light wavelength requirement of 620 nm. Furthermore, the brightness of FROLED at the concentration ratio [3.0:7] may be two times higher because the presence of Rubrene enhances the effective transmission of energy from Alq3 to DCJTB.