Dual Emission from Organic Light-Emitting Diodes Using Deep Red Novel Phosphorescent Iridium(III) Complexes

Abstract

A new phosphorescent Iridium complex, Ir(TMP-TT)₂(acac) was synthesized for organic light-emitting diodes (OLEDs). The ligand, TMP-TT, was synthesized by Suzuki coupling reaction, and Ir(TMP-TT)₂(acac) was synthesized by Nonoyama reaction. The UV-Visible absorption peak and shoulders of Ir(TMP-TT)₂(acac) were measured to be at 366, 420, 490 nm and its photoluminescence (PL) emission spectrums showed blue light-emission peaked 440 nm at 366 nm of UV absorption red light-emission peaked 638 nm at 490nm of UV absorption in chloroform solvent. Optoelectronic properties of device with the structure of ITO / PEDOT (40 nm) / TFB (30 nm) / RH-02 : Ir(TMP-TT)₂(acac) (30 nm : 10%) / Bphen (40 nm) / Liq / Al was measured. The relative intensity of the dual wavelength emissions at 540 nm and 638 nm varied with applying voltage. This study shows that Ir(TMP-TT)₂(acac) can be a strong dopant candidate for the white light-emitting OLEDs.

Keywords:

• Ir(TMP-TT)₂(acac)
• yellow light-emitting
• dual wavelength emitting
• iridium(III) complex

Ackno wledgment

This work was supported by the Technology Innovation Program (201210940002, Materials Development for 50-inches UD OLED TV Using Super Hybrid Process) funded by the Ministry of Knowledge Economy (MKE, Korea).