亚硫酸盐在乙酰二茂铁修饰碳糊电极上的电催化氧化及其电化学动力学性质研究  

Electrocatalytic oxidation of an sulfite at acetylferrocene modified carbon paste electrode and its electrochemical kinetics

作　　者：白莉[1] 高作宁[1] 

机构地区：[1]宁夏大学能源化工重点实验室,化学化工学院,银川750021

出　　处：《分析试验室》2008年第5期80-83,共4页Chinese Journal of Analysis Laboratory

基　　金：宁夏高等学校科学研究(200623)项目资助

摘　　要：研究了亚硫酸盐在乙酰二茂铁（AFc）修饰碳糊电极（AFc/CPE）上的电催化行为。研究结果表明,其在裸碳糊电极（CPE）上的行为比亚硫酸盐在AFc/CPE上的氧化峰电流增加约3倍,氧化峰电位负移360 mV,表明AFc/CPE对亚硫酸盐的电化学氧化具有良好的催化作用。用循环伏安法、计时电流法测定了亚硫酸盐在AFc/CPE上的电极过程动力学参数,测得电荷传递系数α为0.70,电催化氧化反应速率常数k为（4.91±0.05）×104（mol/L）^-1·s^-1。催化氧化峰电流与亚硫酸盐在5.0×10-4～1.1×10^-2mol/L浓度范围内呈良好的线性关系,线性回归方程为Ipa（μA）=1.345＋7.956c（10-3mol/L）,R=0.9988,检出限为2.0×10^-5mol/L。可用于亚硫酸盐的电化学定量测定方法。The electrocatalytical oxidation of sulfite was studied at an acetylferrocene （AFc） modified carbon paste electrode （AFc/CPE） by cyclic vohammetry （CV）. The experimental results showed that the AFc/CPE showed an excellent electrocatalytic activity toward sulfite. The electrocatalytic oxidation peak currents increased about 3 times and the peak potentials shifted negatively 360 mV for sulfite at the AFc/CPE compared with that at the＇CPE. The electrode process kinetic parameters were also investigated by using CV and chronoamperometry （CA）, the electron transfer coemcient a is 0.70, and the reaction rate constant for catalytic oxidation is （4.91 ± 0.05） ×10^4 （mol/L）^-1·s^-1. The catalytic oxidation peak current of sulfite and its concentration had a good linear relationship in the concentration range of5.0× 10^-4 - 1.1 × 10^-2 mol/L with the correlation coefficient of 0.9988, and the detection limit of 2.0 × 10^-5 mol/L. The method can be applied to the electroanalytical determination of the sulfite content.

关 键 词：亚硫酸盐 乙酰二茂铁 碳糊修饰电极 电催化氧化 电化学动力学 

分 类 号：O557.1[理学—热学与物质分子运动论]