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

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, 490nm and its photoluminescence (PL) emission spectrums showed blue light-emission peaked 440nm at 366nm of UV absorption red light-emission peaked 638nm at 490nm of UV absorption in chloroform solvent. Optoelectronic properties of device with the structure of ITO / PEDOT (40nm) / TFB (30nm) / RH-02 : Ir(TMP-TT)(2)(acac) (30nm : 10%) / Bphen (40nm) / Liq / Al was measured. The relative intensity of the dual wavelength emissions at 540nm and 638nm 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.