苯甲酰肼在多壁碳纳米管修饰玻碳电极上的电催化氧化及其电化学动力学性质  

Electrocatalytic oxidation of benzoyl hydrazine at a multi-wall carbon nanotubes modified glassy carbon electrode and its electrochemical kinetics

作　　者：孙玉琴 梁斌 高作宁 赵元弟[2] 

机构地区：[1]宁夏大学能源化工重点实验室,宁夏大学化学化工学院,银川750021 [2]华中科技大学生命科学技术学院,武汉450074

出　　处：《分析试验室》2008年第6期31-34,共4页Chinese Journal of Analysis Laboratory

基　　金：宁夏高等学校科学研究基金(200623);宁夏大学自然科学基金(QN0510)项目资助

摘　　要：研究了苯甲酰肼(BH)在MWCNT/GCE上的电化学行为。实验结果表明,BH在GCE上的直接电化学氧化十分迟缓,无氧化峰出现,但在MWCNT/GCE上BH在0.20 V处出现了一个不可逆氧化峰,且峰电流大幅度增大,表明MWCNT/GCE对BH电化学氧化具有良好的催化作用。同时用计时库仑法(Chro-nocoulometry,CC)和计时电流法(Chronoamperometry,CA)测定了电极过程动力学参数:扩散系数D=8.73×10-5cm2.s-1,电子转移系数α=0.85,电极反应速率常数kf=1.45×10-3s-1。稳态电流-时间实验结果表明,电流响应信号随其浓度成比例增长,响应时间小于6 s,最低响应浓度为1×10-6mol/L。该方法可用于BH电化学定量测定。Electrochemical behaviors of benzoyl hydrazine （BH） on a mtdti-wall carbon nanotubes modified glassy carbon electrode （MWCNT/GCE） were investigated by CV. The experimental results showed that no oxidation peak appears on the GCE. However, on the MWCNT/GCE it appears an irreversible oxidation peak which indicates that MWCNT/GCE can catalyze the electrochemical oxidation of BH very well. At the same time the diffusion coefficient D, electron transfer coefficient a and the electrode reaction rate constant kf were determined, respectively, which give the values of 8.73×10^-5cm^2·s^-1, 0. 85 and 1.45 × 10^-3 s^-1, respectively. According to the experimental results of the amperometric response to time, the current signal of MWCNT/GCE was proportional to BH concentration at response time less than 6 seconds, and the least response concentration is 1 × 10^-6 mol/L, which can be used in BH electrochemical quantitative determination with both low detection limit and high sensitivity.

关 键 词：苯甲酰肼 碳纳米管修饰电极 电催化氧化 电化学动力学 

分 类 号：O657.1[理学—分析化学]