亚硝酸盐在碳纳米管修饰玻碳电极上的电催化氧化及电分析方法研究

Electrocatalytic Oxidation of Nitrite at Multi-wall Carbon Nanotubes Modified Glassy Carbon Electrode and Its Electroanalytical Method

用循环伏安法研究了NO2^-在多壁碳纳米管修饰玻碳电极（MWCNT／GCE）上的电催化氧化行为。采用计时库仑法（CC）和计时电流法（CA）得到了NO2^-在MWCNT／GCE上的动力学参数；利用稳态电流-时间曲线法测定了NO2^-电流响应信号与浓度间的关系。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4s，最低响应浓度为2μmoL／L。用线性扫描伏安法（LSV）对实际工业废水水样进行了分析测定，相对标准偏差（RSD）小于3％，加标回收率在98％～100％之间。

The electrocatalytic oxidation behaviors of nitrite at multi-wall carbon nanotubes modified glassy carbon electrode（MWCNT/GCE） were investigated by cyclic voltammetry （CV）. The kinetic parameters for NO2^- at MWCNT/GCE, such as charge transfer coefficient （α）, diffusion coefficient （D）, electrode reaction rate constant （kf）and reaction orders were obtained by chronocoulometry （CC） and chronoamperometry（CA）, respectively. The relationship between the oxidation peak current and the NO2^- concentration was obtained by the method of amperometric I- t curve. The results showed that the peak current increased proportionally with the NO2^- concentration. The response time was less than 4 s, and the lowest NO2^- concentration response was 2 μmol/L. The NO2^- concentrations in three industrial waste water samples were determined by the linear sweep voltammetry. The relative standard deviation was less than 3% , and the recovery range of the spiked NO2^- was 98% - 100%.