An oxadiazole-functionalized ligand and its yellow-emitting Re(I) complex for organoelectronic application

作者：Ge Hu^*; Lei Guo; Sheng Wei; Shuang Zhang

来源：Optical Materials, 2012, 34(8): 1303-1309.

DOI：10.1016/j.optmat.2012.02.006

• Re(I) complex
• Single crystal
• Electroluminescence
• Photoluminescence
• OLED

A Re(I) complex of Re(CO)(3)(PTO)Br with 2-(pyridin-2-yl)-5-p-tolyl-1,3,4-oxadiazole (PTO) as the diamine ligand is synthesized, resulting in a phosphorescent emitter which contains oxadiazole functional moiety. Single crystal analysis confirms that oxadiazole moiety of PTO ligand participates in the coordination with Re center. Coordination ability difference between N atom from pyridine ring and that from oxadiazole moiety is found. Density functional theory calculation on the crystal suggests that the onset electronic transition owns a mixed character of metal-to-ligand-charge-transfer and ligand-to-ligand-charge-transfer. Upon photon excitation, Re(CO)(3)(PTO)Br exhibits a yellow emission peaking at 549 nm with a short excited state lifetime of 0.15 mu s. Further measurements suggest that Re(CO)(3)(PTO)Br owns HOMO and LUMO energy levels of -5.79 V and -3.49 V and a high decomposition temperature of 322 degrees C. The optimal electroluminescence device using Re(CO)(3)(PTO)Br as the emitting dopant shows an orange light of 598 nm, with a maximum luminance of 4600 cd/m(2) and a maximum current efficiency of 11.5 cd/A.

• 出版日期2012-6
• 单位重庆大学