菲并咪唑衍生物蓝光材料的合成、光物理性质及理论计算

Synthesis,Photophysical Properties and Theoretical Study of Blue Luminescence Materials Based on Phenanthro[9,10-d]Imidazole

合成了两个蓝光材料2-苯基-1H-[9,10-d]菲并咪唑(Phen-PI)和2-吡啶-1H-[9,10-d]菲并咪唑(PyriPI),光物理分析表明Phen-PI和Pyri-PI的最大发射峰分别位于371.5 nm,388.5 nm和403.5 nm,相对量子效率分别为0.383和0.528,激发态衰减寿命分别为3.87 ns和3.68 ns。通过密度泛函理论(DFT)对化合物的前线分子轨道成分和能级分布分析表明,当把Phen-PI中的苯基被吡啶环取代后,Pyri-PI的HOMO能级和LUMO能级分别下降0.09 e V和0.23 e V,同时Pyri-PI的HOMO轨道和LUMO轨道的能级差比Phen-PI减少0.14 e V,在理论层面上解释了Pyri-PI发射光谱的红移。

Two blue luminescence materials 2-phenyl-1H-phenanthro[9,10-d] imidazole（ PhenPI） and 2-pyridin-2-yl-1H-phenanthro[9,10-d] imidazole（ Pyri-PI） were synthesized. The photophysical properties demonstrated the emission peaks of Phen-PI and Pyri-PI are 371. 5,388. 5 and403. 5 nm,the photoluminescent quantum yield is 0. 383 and 0. 528,the fluorescence decay lifetime is 3. 87 ns and 3. 68 ns. The Frontier molecular orbital compositions and distribution for Phen-PI and Pyri-PI were calculated by using density functional theory（ DFT）. The results indicate that the introduction of pyridyl group to phenanthro[9,10-d] imidazole makes HOMO and LUMO of Pyri-PI decline 0. 09 eV and 0. 23 eV respectively,the energy gap between HOMO and LUMO decrease0. 14 eV,which can explaine the red-shift of Pyri-PI emission in theory.