C^N型铱荧光探针检测硝基芳烃及密度泛函理论研究

铱(Ⅲ)配合物因具有斯托克斯位移大、量子产率高、发光寿命长、发射光谱灵活可调及优异的光热稳定性等优点，在分析物发光检测领域具有广阔的应用前景。在2?苯基吡啶上引入三苯胺取代基制备了新型铱(Ⅲ)配合物Ir(ppyTPA)₃，并表征了Ir(ppyTPA)₃的结构、发光及电化学性质，利用Ir(ppyTPA)₃的发光性质实现了对5种常见硝基芳烃的检测，同时研究了检测机理。结果表明，Ir(ppyTPA)₃对3?硝基苯甲酸具有最高的检测效率，检测效率常数K_SV为19.78 L/mmol，检测限低至2.89×10^-3 mol/L。光谱分析及密度泛函理论计算结果表明，Ir(ppyTPA)₃对5种硝基芳烃的检测机理为电荷转移机理。

Detection and Density Functional Theory Study of Nitroaromatic by the C^N Type Iridium Fluorescent Probe

Iridium (III) complexes have broad application prospects in luminescence detection of analyte due to advantages of large Stokes shift, high quantum yields, long luminescence lifetimes, flexible and adjustable emission spectra, and excellent optical and thermal stability. The novel iridium(III) complex Ir(ppyTPA)₃ was prepared by introducing triphenylamine substituent on 2?phenylpyridine, and the structure, luminescence and electrochemical properties of Ir(ppyTPA)₃ were characterized in detail. Then, the luminescence properties of Ir(ppyTPA)₃ were used to detect five common nitroaromatics and the detection mechanism was studied. The results show that Ir(ppyTPA)₃ has the highest detection efficiency to 3?nitrobenzoic acid with the detection efficiency constant K_SV of 19.78 L/mmol. And the detection limit is as low as 2.89×10^-3 mol/L. Spectral analysis and density functional theory calculations show that the detection mechanism of Ir(ppyTPA)₃ for the five nitroarenes was the charge transfer mechanism.