N,N-(diphenylamino)fluorenylstyrene derivatives with the various heteroatom-containing moieties for blue organic light-emitting diodes.

A series of blue fluorescent materials 1-6 based on N, N-diphenyl aminofluorene styryl derivatives with six heteroatoms (PhOPh, PhSPh, PhSePh, PhPPh2, thiophene and dibenzothiophene), were synthesized and multilayer devices were fabricated. Interestingly, the EL efficiencies were very sensitive to the structural features of dopants in the emitting layers. Particularly, by using 1 as a dopant in emitting layer, a high-efficiency blue OLED was fabricated, showing the maximum luminance of 10420 cd/m2 at 11 V, the luminous efficiency of 8.6 cd/A at 20 mA/cm2, the power efficiency of 3.4 Im/W at 20 mA/cm2 and had a blue color with the CIE coordinates of (0.147, 0.156) at 8.0 V.