Application： N-([1,1′-biphenyl]-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine (BCFN) is an electron-rich material, with the HOMO energy level of 5.3 eV, the LUMO energy level of 2.2 eV and high hole mobility of 5.43 × 10-5 cm2V-1s-1. As a result, it is used as a hole-transport and hole-injection material in organic light-emitting diodes. BCFN has shown its advantages in improving the hole mobility of polymer-based hole transport layer; lower driving voltage of device, better efficiency, and higher EQE due to exciplex formation by utilizing in EML; and better device lifetimes in the combination of Ir(piq)2(acac) to act as an electron scavenger layer for an reported device. BCFN is a good morphologically stable material with Tg of 125 °C and Td of 375 °C. With a ET of 2.58 eV, BCFN is also a very good charge transporting layer material due to its large band gap (Eg = 3.1 eV) 2 for green, red and white phosphorescent organic light-emitting diodes (PhOLEDs). OLED Device Performance: BCFN increase the hole transport mobility of PVK (pure PVK: 2.09×10-9 V cm-1 S-1; 30% of BCFN in PVK: 9.86×10-7 V cm-1 S-1; 50% of BCFN in PVK: 1.15×10-5 V cm-1 S-1): 1. ITO/PEDOT:PSS (40 nm)/PVK:BCFN (3:7, 20 nm)/BCFN:PFO (x:1-x, 80 nm)/CsF (1.5 nm)/Al (120 nm) Color: Blue BCFN in combination of ET1 to act as EML in forming exciplex and improve device performance: 2. ITO/HIL/HTL/(ET1+P1) or (ET1+BCFN+P1(doped)/ETL/ LiF/Al Color: red Device emission area of 81cm2, and at 1000 cd m-2, the efficiency exceeds 200 lm/W and the EQE exceeds 50 %. lifespan@95: from 71h to 133h BCFN in combination with Ir(piq)2(acac) as electron scavenger layer: 3. ITO/NDP series in BCFN (3wt.%, 10nm)/BCFN(160nm) or BCFN(130nm)+BCFN:Ir(piq)2(acac)(2wt.%, 10nm)+BCFN(20)/ [Ir(TMSBppy)ppy2]:BPTZBC (10 wt.%, 40nm))/ TPBi:Liq (1:1 wt. % ratio, 36nm)/ Liq (0.1nm)/Al (60 nm) Color: yellow Efficiencies are not affected. lifespan@95: from 71h to 133h