酒石酸插层水滑石修饰ITO电极伏安法测定水中铅

将酒石酸插层水滑石(TA-HT)分散于壳聚糖(CS)溶液中，制备了新型的薄膜修饰电极。采用X射线衍射仪(XRD)、红外吸收光谱仪(IR)对酒石酸插层水滑石进行了表征，循环伏安法(CV)对修饰电极进行了电化学表征，线性扫描溶出伏安法(LSSV)研究Pb²⁺在修饰电极上的电化学行为。与裸电极相比，修饰电极的电化学活性得到很大的提高。Pb²⁺在5～180μg/L的浓度范围内与其峰电流呈良好的线性关系，相关系数为0.997，检测限可达1μg/L。测定0.1mg/LPb²⁺，当相对误差在±5%范围时，200倍Na⁺、K⁺、F^-、NO₃^-，100倍Zn²⁺、Fe³⁺、Ni²⁺、Co²⁺，10倍Bi³⁺、Ca²⁺，5倍Cu²⁺不干扰测定。方法用于实际池塘水样中Pb²⁺的测定，测定值与原子吸收光谱法的测定值基本一致，回收率在98.0%～102.5%之间。

Determination of lead in water by voltammetry with tartaric acid intercalated hydrotalcite-modified ITO electrode

The tartaric acid intercalated hydrotalcite (TA-HT) was dispersed in chitosan (CS) solution to prepare a new type of film modified electrode. X- Ray diffractometer (XRD),infrared absorption spectrometer (IR) were employed for characterization of tartaric acid intercalated hydrotalcite,cyclic voltammetry (CV) was used for the electrochemical characterization of the modified electrode,and linear sweep stripping voltammetry (LSSV) was adopted to investigate the electrochemical behavior of Pb²⁺ on the modified electrode. Compared with the bare electrode,the modified electrode achieved an increased electrochemical activity. Pb²⁺ in the concentration range of 5 - 180 μg/L constituted a fine linear relation with its peak current,with a correlation coefficient of 0.997 and the detection limit of up to 1 μg/L. In determination of 0.1 mg/L Pb²⁺,when the relative error was in the ± 5% range,200-fold Na⁺,K⁺,F^- and NO₃^-,100-fold Zn²⁺,Fe³⁺,Ni²⁺ and Co²⁺,10-fold Bi³⁺ and Ca²⁺ and 5-fold Cu²⁺ did not interfere with the determination. The proposed method was applied to the determination of Pb²⁺ in actual pond water samples and the measured values were consistent with those obtained by atomic absorption spectrometry,with recoveries between 98.0%-102.5%.