Eunyoung Nam, Jun Ho Kim, B. Kim
Apr 2, 2004
Citations
0
Influential Citations
27
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
Tris(1-phenyl-κC 1 -pyrazolato-κN 2 )iridium (Ir(ppz) 3 ) was prepared and its luminescence properties were investigated for the application to organic light-emitting devices (OLEDs). The photoluminescence (PL) spectra of Ir(ppz) 3 in dichloromethane showed a peak at 437 nm at room temperature. The luminescent lifetime of an Ir(ppz) 3 film doped in CBP was found to be 218 ns, which indicated that its emission is phosphorescent. OLEDs were fabricated with doped films of Ir(ppz) 3 in several hosts, and the electroluminescence (EL) peak was observed at 450 nm. The luminance of OLEDs was pure blue, with the CIE coordinates of x = 0.158, y = 0.139 at 100 cd/m 2 , but luminous efficiencies were low since the LUMO of Ir(ppz) 3 is higher than those of the hosts used.