羧基化多壁碳纳米管修饰碳糊电极用于溶出伏安法测定铋（Ⅲ）量

摘要

将羧基化的多壁碳纳米管滴涂在碳糊电极表面上，应用羧基化的多壁碳纳米管修饰碳糊电极（MWCNT_COOH／CPE）测定铋（Ⅲ）时，将试液在0．1mol·L^-1叫盐酸溶液中在-500mV处预富集120s，使铋（HI）与1-（4-磺酸基苯基）-3-[4（苯基偶氮）-苯基]-三氮烯（SPAP]r）生成络合物，然后在-500-500mV范围内扫描，使络合物中的铋（Ⅲ）从电极上溶出，实现了铋离子的溶出伏安法测定。在-32mV处可得铋离子的氧化峰电位，其峰电流值与铋（Ⅲ）浓度在1．0×10^-5-4．0×10^-7mol·L^-1范围内呈线性关系，检出限（3s／N）为3．0×10^-10mol·L^-1。%A carboxylated multi wall carbon nanotubes （MWCNT-COOH） modified carbon paste electrode （CPE） was prepared by doping MWCNT COOH on the surface of CPE. In the determination of Bi^3＋ -ion, the test solution in 0. 1mol·L^-1 HC1 was pretreated by pre-enrichment for 120 s at - 500 mV, to have the Bi^3＋- ion complexed with 1-（4-sulfo-phenyl）-3-[4-（phenylazo） phenyl]triazene （SPAPT）. Bismuth ion in the complex was then stripped from the electrode by stripping vohammetry by scanning in the range from -500 to 500 mV, and the oxidation peak potential of bismuth ion was observed at 32 mV, where linear relationship between values of peak current of Bia＋ ion and its concentration was obtained in the range of 1.0X10 ^-9-4. 0× 10 ^-7mol·L^-1. Detection limit （3S/N） of the method found was 3.0×10^-10 mol·L^-1.