Eu3+掺杂TiO2荧光探针的制备及对氯氰菊酯的检测应用

以钛酸四丁酯为前体,采用液相法制备了水溶态纳米Eu3+掺杂TiO2荧光探针,并对其发光性质进行了研究。通过紫外吸收和荧光光谱研究了它和氯氰菊酯之间的相互作用,结果发现,氯氰菊酯对Eu3+掺杂TiO2的荧光具有猝灭作用,根据Stern-Volmer猝灭方程,计算出其猝灭常数为1.017×1011 L/(mol.s),并讨论了猝灭机理。依据氯氰菊酯浓度和Eu3+掺杂TiO2的荧光强度成正比,建立了一种快速检测农药的新方法。其检测范围为2.5×10-10～2.5×10-7mol/L,检出限为2.5×10-11mol/L,回收率在89.25%～93.55%之间。

Preparation of Eu3+ doped with TiO2 fluorescent probe and its application on the detection of cypermethrin

Using tetrabutyl titanate as a precursor,the nanometer Eu3+ doped TiO2 was prepared by sol-gel method,and the property of luminescence of nano-powder was studied.The interaction of cypermethrin with Eu3+-TiO2 was studied by absorption and fluorescence spectroscopy.The results indicated that the fluorescence intensity of Eu3+-TiO2 was quenched by cypermethrin and the quenching rate constant(kq)was 1.017×1011 L/(mol?s) according to the Stern-Volmer equation,and the mechanism of quench had been discussed.A new rapid method for detection of pesticides was established according to that the fluorescence intensity of Eu3+-TiO2 was proportional to cypermethrin concentration.The range of detection was 2.5×10-10—2.5×10-7 mol/L,the detection limit(3σ)was 2.5×10-11 mol/L and the recovery was 89.25%—93.55%.