Abstract

A blue-emitting poly(2,7-carbazole) having a naphthyl substituent at the N-position (PNCz) was newly synthesised by the Yamamoto method and used to fabricate an organic light emitting diode (OLED). PNCz was highly soluble in common organic solvent with the number average molecular weight (Mn) of 17600 and good thermal stability, with the decomposition temperature higher than 390 °C. PNCz exhibited intense blue photoluminescence with emission peak maxima at 415 nm in CHCl3 and 428 nm in the film state, and the fluorescence quantum efficiency in CHCl3 was extremely high (Φfl = 0.99). The HOMO level estimated by cyclic voltammetry was −5.50 eV and the band gap estimated from an absorption edge was 2.72 eV. The OLED device with a configuration of ITO/PEDOT:PSS/PNCz/CsF/Al exhibited bluish emission with several hundreds cd m−2 and CIE index (x = 0.20, y = 0.21) at low operating voltages in the range of 6–7 V and greenish emission with about 3000 cd m−2 and CIE index (0.25, 0.44) under high operating voltage around 11 V.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.