Exceedingly efficient deep-blue electroluminescence from new anthracenes obtained using rational molecular design

Abstract

9,10-Bis(3′,5′-diphenylphenyl)anthracene [MAM], 9-(3′,5′-diphenylphenyl)-10-(3‴,5‴-diphenylbiphenyl-4″-yl)anthracene [MAT], and 9,10-bis(3″,5″-diphenylbiphenyl-4′-yl)anthracene [TAT] were newly synthesized through boration and Suzuki aryl–aryl coupling reactions. We have demonstrated that the EL performance of blue-light emitters can be optimized and improved by varying the chemical structures of the side groups. In the thin film state, the three materials exhibit PLmax values in the range of 439–445 nm. MAM, MAT, and TAT all have high Tg values above 120 °C; TAT has the highest Tg value, above 150 °C. This is twice as high as that of DPVBi (64 °C) and is much higher than that of MADN (120 °C) as well. It also exhibits excellent color coordinates (0.156, 0.088), which are very close to the NTSC blue standard, and an external quantum efficiency of 7.18%, twice that of MADN, which are the best reported results for deep-blue OLED emitters.