Ambipolar Phosphine Derivatives to Attain True Blue OLEDs with 6.5% EQE

Tutkimustuotos: Lehtiartikkelivertaisarvioitu

Tutkijat

  • Ilya Kondrasenko
  • Zheng Hua Tsai
  • Kun You Chung
  • Yi Ting Chen
  • Yana Yu Ershova
  • Antonio Doménech-Carbó
  • Wen Yi Hung
  • Pi Tai Chou
  • Antti Karttunen

  • Igor O. Koshevoy

Organisaatiot

  • University of Eastern Finland
  • National Taiwan Ocean University
  • National Taiwan University
  • Soochow University, Taipei
  • Universidad de Valencia

Kuvaus

A family of new branched phosphine derivatives {Ph2N-(C6H4)n-}3P → E (E = O 1-3, n = 1-3; E = S 4-6, n = 1-3; E = Se 7-9, n = 1-3; E = AuC6F5 4-6, n = 1-3), which are the donor-acceptor type molecules, exhibit efficient deep blue room temperature fluorescence (λem = 403-483 nm in CH2Cl2 solution, λem = 400-469 nm in the solid state). Fine tuning the emission characteristics can be achieved varying the length of aromatic oligophenylene bridge -(C6H4)n-. The pyramidal geometry of central R3P → E fragment on the one hand disrupts π-conjugation between the branches to preserve blue luminescence and high triplet energy, while on the other hand provides amorphous materials to prevent excimer formation and fluorescence self-quenching. Hence, compounds 2, 3, 5, and 12 were used as emitters to fabricate nondoped and doped electroluminescent devices. The luminophore 2 (E = O, n = 2) demonstrates excellently balanced bipolar charge transport and good nondoped device performance with a maximum external quantum efficiency (EQEmax) of 3.3% at 250 cd/m2 and Commission International de LEclairage (CIE) coordinates of (0.15, 0.08). The doped device of 3 (E = O, n = 3) shows higher efficiency (EQEmax of 6.5, 6.0 at 100 cd/m2) and high color purity with CIE (0.15, 0.06) that matches the HDTV standard blue. The time-resolved electroluminescence measurement indicates that high efficiency of the device can be attributed to the triplet-triplet annihilation to enhance generation of singlet excitons.

Yksityiskohdat

AlkuperäiskieliEnglanti
Sivut10968-10976
Sivumäärä9
JulkaisuACS Applied Materials and Interfaces
Vuosikerta8
Numero17
TilaJulkaistu - 4 toukokuuta 2016
OKM-julkaisutyyppiA1 Julkaistu artikkeli, soviteltu

ID: 4371227