新型绿色磷光铱配合物的合成及其光物理性能研究

合成并表征了以2-苯基吡啶为第一配体,水杨酸及其衍生物为第二配体,以铱为内核的新型配合物(ppy)_2Ir(LX)(ppy=2-苯基吡啶,LX=水杨酸Sal、4甲基水杨酸MSal、4-三氟甲基水杨酸FSal)。对其分子结构、光物理性能及热稳定性进行了测试和分析。结果表明,室温下在二氯甲烷溶液中(ppy)_2Ir(LX)(LX=Sal,MSal,FSal)的吸收峰分别在270,370,450及484 nm附近,其中前2个吸收峰应归属于第一配体2-苯基吡啶的~1π—π~*跃迁和水杨酸配体到2-苯基吡啶的电荷转移跃迁,在450及484 nm附近的吸收峰,应该归属于金属到配体的电荷转移(~1MLCT和~3MLCT)跃迁和配体~3π—π~*跃迁的混合;其PL发射峰最大波长分别为520,522,510 nm;(ppy)_2Ir(Sal)和(ppy)_2Ir(MSal)的发射主要来源于三重态~3MLCT的辐射跃迁,而(ppy)_2Ir(FSal)的发射主要来源于水杨酸到2-苯基吡啶的电荷转移态的辐射跃迁,也有单重态~1MLCT和三重态~3MLCT的辐射跃迁的贡献。其量子效率分别为0.37,0.33,0.29,热分解温度为306～328℃。(ppy)_2Ir(LX)是一组热稳定性较好的高效有机磷光材料,可用于有机电致发光器件中。

New Highly Phosphorescent Heteroleptic Tris-Cyclometalated Iridium (Ⅲ) Complexes: Synthesis and Photophysical Characterization

New heteroleptic tris-cyclometalated iridium( HI) complexes (ppy)_2Ir(LX) (ppy=2-phenylpyridine, LX=Sal (salicylic acid), Msal (4-methylsalicylic acid), FSal(4-trifluoro methyl salicylic acid)) was synthesized and characterized. The molecular structure, photophysical properties and thermal stability were tested and analyzed. The results show that the absorption peaks were located around 270, 370, 450 and 484 nm respectively at room temperature. The two former peaks at 270 and 370 nm should belong to ~1_π-π~* transition at ppy and transition from salicylic acid ligands to 2-phenylpyridinejThe peaks around 450 and 484 nm can be assigned to the charge transfer transition from Ir to ligand (~1MLCT and ~3MLCT) and ~3_π-π~* transition respectively. The PL emission peaks were located at 520, 522, and 510 nm, respectively. The emission of (ppy)_2lr(Sal) and (ppy)_2Ir (MSal) was mainly ascribed to the radiation transition of triple state ~3MLCT, while the emission of (ppy)~2Ir(FSal) was mainly from the radiation transition between Sal and ppy, partly from the radiation transition of single state ' MLCT and triple state ~3MLCT. The quantum efficiencies of these complexes were 0. 37, 0. 33 and 0. 29 respectively. The thermal decomposition temperature was from 306 to 328 ℃. (ppy)_2 Ir(LX) , being a series of efficient phosphorescent materials with good thermal stability, can be used in the organic electroluminescent devices.