纳米银修饰石墨电极伏安法测定过氧化氢

Silver nanoparticles modified graphite electrode for voltammetric detection of hydrogen peroxide

基于纳米银对过氧化氢分解的催化作用,用恒电位沉积法将银纳米粒子固定在石墨电极上,制备了一种过氧化氢传感器.用循环伏安法对H2O2进行测定,并对可能的测定机理进行探讨.选择了过氧化氢传感器测定H2O2的最适pH为6.0,在1.1×10-5～2.2×10-2mol/L范围内,还原峰电流与H2O2浓度呈良好线性关系.该传感器具有制备简易、成本低廉、响应快、灵敏度高、稳定性好等特点,具有较好的应用前景.

A novel amperometric sensor for the detection of hydrogen peroxide（H2O2） was prepared by electro-deposition of silver nanoparticles on the graphite electrode.The silver nanoparticles was characterized with UV-Vis spectroscopy and scanning electron microscopy.The electrochemical performances of the electrode were studied by cyclic voltammetry.The silver nanoparticles immobilized on the graphite electrode exhibited an excellent electrocatalytic response toward reduction of H2O2.The resulting Ag nanoparticles modified sensor showed a good sensitivity with a linear range of 1.1×10-5 ~ 2.2 ×10-2 mol/L（correlation coefficient r=0.996 9）.Its detection limit was 3.8×10-6 mol/L.The preparation process of the proposed H2O2 sensor was convenient,and the H2O2 sensor showed high sensitivity,low detection limit and good stability.