羟基磷灰石/离子液体混合膜修饰电极的制备及其应用于水中痕量镉离子的高选择性测定  

Preparation of Hydroxyapatite/Ionic Liquid Composite Film Modified Electrode and Its Application to the Highly Selective Determination of Trace Cadmium in Water

作　　者：潘壮英[1] 马荣娜[1] 李静[1] 刘燕[1] 赵倩[1] 王国涛[1] 王怀生[1] 

机构地区：[1]聊城大学化学化工学院,聊城252059

出　　处：《化学学报》2009年第23期2721-2726,共6页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.20575024;20775031);山东省"泰山学者"建设工程专项经费资助项目

摘　　要：利用溴代十六烷基三甲基铵(CTAB)为模板,合成制备了棒状羟基磷灰石颗粒,并以SEM,XRD,IR等手段进行了表征.用制备的羟基磷灰石与自制的离子液体([BMIM]PF6)充分混合涂覆在玻碳电极表面制备了羟基磷灰石/离子液体修饰电极,研究了镉离子在该修饰电极上的富集和电化学行为.结果发现,羟基磷灰石对镉离子有较好的富集作用,而离子液体则可以在开路条件下使镉离子还原为金属镉,氧化扫描时可以得到镉的灵敏氧化溶出峰,以此为基础建立了一种高选择性地测定痕量镉离子的新方法,该方法可以较好地避免铅、汞、银等重金属离子的干扰,对镉离子检出限可达2.0×10-8mol·L-1,在4.0×10-8～2.2×10-7mol·L-1的浓度范围内,氧化溶出峰电流与Cd(II)的浓度呈良好的线性关系.该研究有望在环境检测和环境治理方面发挥重要作用.Stick-like hydroxyapatite particles were synthesized using cetyltrimethylammonium bromide as template and characterized with SEM, XRD and IR. The hydroxyapatite/ionic liquid modified electrode was prepared by coating the mixture of hydroxyapatite particles and the ionic liquids （[BMIM]PF6） on the glassy carbon electrode surface. The accumulative and electrochemical behavior of Cd（Ⅱ） on the modified electrode was investigated and the results showed that Cd（Ⅱ） could be accumulated on the hydroxyapatite surface and reduced to Cd by the ionic liquid at the open-circuit. When the potential was scanned to positive direction, a sensitive stripping peak was obtained. Therefore, a novel method was developed for the highly selective determination of trace cadmium in water samples based on the oxidative stripping. The interferences from lead, mercury, silver and other common metal ions were not found in this method. There was a good liner relationship between the stripping peak current and Cd（Ⅱ） concentration in the range of 4.0 × 10^-8-2.2 × 10^-7 mol· L^-1 with the detection limit of 2.0× 10^-8 mol·L^-1 Cd（Ⅱ）. This study should have potential application to environmental monitoring and environmental treatment.

关 键 词：羟基磷灰石 离子液体 镉离子 修饰电极 

分 类 号：TB383.4[一般工业技术—材料科学与工程]