2-硝基苯酚在蒙脱石修饰碳糊电极上的电化学行为研究

Study on the Electrochemical Behavior of 2 - nitrophenol at the Sodium Montmorillonite Modified Carbon Paste Electrode

用微分脉冲伏安法研究了2-硝基苯酚在蒙脱石修饰碳糊电极上的电化学还原行为,提出了一种直接检 测2-硝基苯酚的伏安分析方法．优化了影响2-硝基苯酚伏安响应的各种参数,例如支持电解质、pH值、蒙脱石 用量、富集电位和时间．在1×10-7-2×10-5mol／L浓度范围内,峰电流与浓度呈良好的线性关系,开路富集4 min 后,检出限(3倍信噪比)为8×10-9mol／L．2×10-4mol／L ×2-硝基苯酚平行测定8次的相对标准偏差为3．8％．用 该修饰电极测定了实际水样中2-硝基苯酚,平均回收率为101．22％．

The electrochemical reduction of 2 - nitrophenol at the sodium montmorillonite modified electrode by differential pulse voltammetry was sdudied, and a method for the direct voltammetric determination of 2 - nitrophenol was proposed. The parameters that influence the voltammetric response of 2 - nitrophenol, such as supporting elec- trolyte, pH values, amounts of sodium montmorillonite, accumulation potential and time, were examined. A linear relationship between peak current and concentration was obtained in the range from 1 × 10ε-7 - 2 × 10^-5mol/L,and the detection limit（ signal to noise = 3） is 8 × 10^-9 mol/L after 4 rain open -circuit accumulation. The cofficiont of variation, which determined at × 10^-5 mol/L 2 - nitrophenol , is 3.8% （ n = 8） . Using the sodium montmorillonite modified carbon paste electrode ,2 -nitrophenol in the water samples were detected , and the average recovery is 101.22%.