基于(Sn,Ba,La)·(PO_4)_3Cl·Eu纳米颗粒荧光猝灭法测定废水中Cr(Ⅵ)

Determination of trace Cr(Ⅵ) by fluorescence quenching with (Sn,Ba,La)·(PO_4)_3 Cl·Eu nanoparticles

基于Cr(VI)对(Sn,Ba,La)5.(PO4)3Cl.Eu纳米颗粒的荧光猝灭作用,建立了用琼脂溶液来固定分散(Sn,Ba,La)5.(PO4)3Cl.Eu纳米颗粒并用于测定水中微量Cr(VI)的荧光分析新方法.研究表明:Cr(Ⅵ)离子对固定于琼脂溶液中的(Sn,Ba,La)5.(PO4)5Cl.Eu纳米颗粒有荧光猝灭作用.在pH=9.0的条件下,测定的荧光最大激发波长和发射波长分别为271nm和447nm,测定Cr(VI)浓度的线性范围为4.0×10-6mol/L～1.4×10-4mol/L,检测限为2.99×10-6mol/L,回收率为98.9%～103.0%.方法具有良好的重现性和选择性,一些常见金属离子不干扰测定.应用于环境水中Cr(Ⅵ)离子含量的测定,结果满意.

A new and sensitive method for determining trace Cr （VI） was developed by using well dispersed （Sn,Ba,La） · （PO4 ）3Cl · Eu nanoparticlesin an agar solution based on the fluorescence quenching. The maximum excitation and emission wavelengths of the nanoparticles were 271 nm and 447 nm, respectively. This method showed good linear response in the range from 4.0×10^-6 mol/L - 1.4×10^-4moL/L Cr（VI） with recovery of 98.9% - 103.0%. Some common metal ions did not interfere the detection, shaving good potential in determining Cr（VI） in waste water.