[20a-145-1~12] 12.4 Organic light-emitting devices and organic transistors

[20a-145-1] A novel series of hole transport materials containing [1]benzothieno[3,2-b][1]benzothiophene (BTBT) moieties for organic light-emitting devices

〇Takayoshi Kikuchi¹, Hisahiro Sasabe^1,2,3, Yuichiro Watanabe³, Hiroshi Katagiri^1,2,3, Junji Kido^1,2,3 (1.Grad. Schol. of Org. Mater. Sci., Yamagata Univ., 2.Research Center for Organic Electronics (ROEL), 3.Frontier Center for Organic Materials (FROM))

Keywords:OLED, hole transport material

In this work, we developed a novel series of HTMs aiming higher thermal stability and higher hole mobility than those of NPD by introducing [1]benzothieno[3,2-b][1]benzothiophene (BTBT) moieties. BTBT is famous in organic field effect transistor (OFET), and has realized excellent hole mobility for OFET applications. A novel HTM containing BTBT showed superior thermal stability with T_g of 155 ^oC, and good hole transport property in OLEDs. An OLED with a structure of [ITO / 2,3,6,7,10,11-Hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HATCN) / novel HTM / 9,9'-diphenyl-9H,9'H-3,3'-bicarbazole (BCzPh) / tris(2-phenylpyridinato)iridium(III) (Ir(ppy)₃)-doped BCzPh / 3,3”,5,5’-tetra(3-pyridyl)-1,1’;3’,1”-terphenyl (B3PyPB) / 8-quinolinolato lithium (Liq) / Al] were fabricated. The device exhibited driving voltage of 3.7 V and EQE of 17% at 1000 cd/m². These performances suggest the potential usefulness of these HTMs for OLEDs.