Microwave Synthesis of Iridium(III) Complexes: Synthesis of Highly Efficient Orange Emitters in Organic Light-Emitting Devices

• Published in: Japanese Journal of Applied Physics Vol. 43; no. 5R; p. 2733
• Main Authors: Saito, Kaori, Matsusue, Noriyuki, Kanno, Hiroshi, Hamada, Yuji, Takahashi, Hisakazu, Matsumura, Takeko
• Format: Journal Article
• Language: English
• Published: 2004
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.43.2733

Microwave synthesis of tris-ortho-metalated Ir(III) complexes was performed and resulted complexes were applied to the electrophosphorescent devices. For synthesis of Ir(ppy) 3 , the product was obtained by 30 min. microwave irradiation. That is microwave irradiation reduced the reaction time to 1/20 of that under conventional heating. Furthermore, we succeeded the rapid microwave synthesis of tris(2-phenyl-1-quinoline)iridium(III), Ir(phq) 3 , which is hard to synthesis by conventional method. An electrophosphorescent device with Ir(phq) 3 as a dopant in emitting layer was developed. It demonstrated a high-efficient orange emission with maximum luminous efficiency of 33.4 cd/A and a power efficiency of 11.7 lm/W at 800 cd/m 2 . The color of emission corresponds to CIE coordinates x =0.56, y =0.43. The device showed a projected operational lifetime, namely T 1/2 , of 6500 h at an initial brightness of 1500 cd/m 2 under constant dc drive.