Novel pyrene derivatives: Synthesis, properties and highly efficient non-doped deep-blue electroluminescent device

Two novel pyrene derivatives 1,6-bis(3,5-diphenylphenyl)pyrene (BDPP) and 1,6-bis(2-naphthyl)pyrene (BNP) were synthesized and characterized by 1H NMR, 13C NMR, mass spectrum and elemental analysis. The compounds BDPP and BNP exhibit bright blue emission with high fluorescence quantum yields. The quantum chemical calculations show that BDPP has a higher non-coplanar structure compared to BNP. The electrochemical properties and energy levels of the compounds were investigated by cyclic voltammetry. BDPP exhibits a high thermal stability with the decomposition temperature of 440 °C and the glass transition temperature of 139 °C. The non-doped device based on BDPP achieves a very stable deep-blue emission with a maximum efficiency of 3.26 cd/A. The 1931 CIE coordinates (0.15, 0.11) of this device are very close to the National Television System Committee blue standard.

► Two novel blue materials BDPP and BNP were synthesized and characterized. ► BDPP has a highly non-coplanar structure and a high thermal stability. ► A stable and highly efficient non-doped deep-blue device was fabricated.