分别采用共沉淀法和溶胶-凝胶法合成了MgAl水滑石和锐钛矿型纳米TiO2,进行了XRD和TG-DTA表征.将两者按一定比例混合,制备成修饰的玻碳电极.采用示差脉冲伏安法详细研究了Pb2+在修饰玻碳电极上的电化学响应行为,并对各种实验影响因素进行了优化.结果表明,在0.1 moL/L的NaAc-HAc缓冲溶液中,当pH=4,MgAl水滑石与TiO2的质量比为1:1,制膜的滴涂量为9μL时,1×10-5 mol/L的Pb2+在-1.2 V富集1.5 min后,进行电化学扫描,Pb2+在大约-0.47 V出现一灵敏尖锐的溶出峰,溶出峰电流与其浓度在1×10-9~2×10-7 mol/L范围内呈良好线性关系,检出限为1.0×10-10 mol/L,表明复合膜修饰玻碳电极检测铅离子效果很好.%MgAl hydrotalcite and anatase type nano titanium dioxide were prepared by coprecipitation method and sol-gel method, respectively. The prepared samples were characterized by XRD and TG-DTA. The modified glassy carbon electrode was prepared by using both of them. The electrochemical behavior of Pb2+on the modified glassy carbon electrode was studied by stripping voltamme-try in details. The results indicated that the optimum condition was as follows:in 0. 1 moL/L NaAc-HAc buffer solution with pH=4, when the mass ratio of MgAl-HT : TiO2=1 : 1 and the amounts of composite films is 9 μL,after 1. 5 min enrichment at-1. 2 V, a sensitive stripping peak appeared at-0. 47 V at the chemical curve of 1×10-5 mol/L Pb2+solution. And the stripping peak cur-rent was linear with concentration of Pb2+ in the range of 1×10-9 ~2×10-7 mol/L,and the detection limit was 1×10-10 mol/L.
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