Novel 2,4-difluorophenyl-functionalized triphenylamine and its dimer, namely tris(2',4'-difluorobiphenyl-4- yl)-amine (3FT) and N-4, N-4, N-4', N-4'-tetrakis-(2',4'-difluorobiphenyl-4-yl)-biphenyl-4,4'-diamine (4FDT), have been synthesized and characterized. The device with the configuration of ITO/4FDT/Alq(3)/LiF/Al yields maximum current efficiency of 4.3 cd/A. Moreover, with 4FDT as the hole-injecting layer, the maximum efficiency and luminance of the device was further improved to be 5.0 cd/A and 19880 cd/m(2), respectively. The good performance of devices with 4FDT as HTL or HIL was attributed to the incorporation of the strong electron-withdrawing fluorinated substituents into the arylamine moiety, which reduced holes mobility of HTL and HIL and then balanced the injected carriers in devices. (C) 2011 Elsevier B. V. All rights reserved.