Fluorinated 9,9'-spirobifluorene derivative as host material for highly efficient blue fluorescent OLED

We report a newly synthesized blue fluorescent fluorinated 9,9'-spirobifluorene based host material Spiro-(3,5)-F and its application in organic light-emitting device. Spiro-(3,5)-F has a high thermal stability with the decomposition temperature of 395 °C and the glass transition temperature of 145 °C. An organic light-emitting device using Spiro-(3,5)-F as host and 4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'-biphenyl as dopant material exhibits a low turn-on voltage of 3.5 V, a maximum current efficiency of 6.51 cd A−1, and a maximum external quantum efficiency of 3.85%, implying good energy transfer and device performances. Moreover, this device exhibited low efficiency roll-off at high luminance and stable blue emission.