A novel blue-emitting Ir(III) complex with short excited state lifetime: Synthesis,structure, photophysical property,and electrophosphorescence performance

In this paper, we synthesize a triphenylamine-derived cyclometalating ligand of (4-benzothiazol-2-yl-phenyl)-diphenyl-amine (referred as BPDA) and its corresponding Ir(III) complex of (BPDA)₂Ir(acac) (acac=acetylacetone). The photophysical property, molecular structure, thermal property and electroluminescence performance of (BPDA)₂Ir(acac) are investigated in detail. It is found that (BPDA)₂Ir(acac) is an efficient emitter with high thermal stability and short excited state lifetime. The emission of (BPDA)₂Ir(acac) changes from deep blue (417 nm) to bluish green (500 nm) upon addition of different solvents. We also investigate its electrophosphorescence performance. A maximum electroluminance of 8820 cd/m² peaking at 494 nm is achieved, with the highest device efficiency of 1.72 cd/A.