Synthesis, Characterization and Optical Properties Based on a Novel Re(I) Emitter with Bulky Building Block
A novel rhenium complex material, i.e., Re-APPP, (APPP, 2,3-acenaphtho[1,2-b]pyrazino [2,3-f][1,10]phenanthroline) was designed, synthesized in five steps from commercially available starting materials and characterized by FTIR, 1H NMR and mass spectroscopy. The photophysical properties of this complex were studied. The absorption bands centered at ca. 326, 366 and 450nm of Re-APPP were attributed to the ligand-centered p→p* transition and the metal-to-ligand charge transfer dπ(Re)→π*(APPP) transition, respectively. Re-APPP was thermally stable with high decomposition temperature of 302°C. The organic light-emitting diodes using Re-APPP as a dopant emitter with the structures of ITO/m-MTDATA(10nm)/NPB(20nm)/CBP: Re-APPP(30nm)/BCP(10nm)/Alq3(30nm)/LiF(1nm)/Al(100nm) were fabricated and a broad electroluminescent peak at 550nm was observed. More importantly, the devices exhibited very small efficiency roll-off of only ca.45% which was probably attributed to its short luminescent lifetime.
Pengcheng Wang, Liqun Ai, Yungang Li, Xiaoming Sang and Jinglong Bu
T. N. Zang et al., "Synthesis, Characterization and Optical Properties Based on a Novel Re(I) Emitter with Bulky Building Block", Advanced Materials Research, Vols. 295-297, pp. 373-377, 2011