Au/L-Met/GC电极的H2O2电催化氧化

在无额外的添加剂和保护剂的情况下，以柠檬酸钠还原氯金酸制得链状金纳米粒子，使用扫描电子显微镜（SEM）和透射电子显微镜（TEM）观察样品. 层层自组装技术可将金纳米粒子自组装，并分别以L-甲硫氨酸（L-Methionine，L-Met）、硫脲（Thiourea，TU）、丙烯基硫脲（Allyl thiourea，ATU）和聚乙烯吡咯烷酮（Polyvinylpyrrolidone，PVP）交联剂自组装于玻碳基底，即得金纳米粒子修饰电极. 以Fe(CN)₆]^3-/4-氧化还原电对为探针，考察该修饰电极的电化学性质. Au/L-Met/GC电极有最佳电化学性能，循环伏安曲线和计时电流曲线测试表明，Au/L-Met/GC电极的H₂O₂电催化氧化有较高的灵敏度，线性范围2×10^-7 ~ 3×10^-3 mol·L^-1，检出限6.67×10^-8 mol·L^-1.

Electro-Catalytic Oxidation of Hydrogen Peroxide on Au/ L-methionine /GC Electrode

The modified electrodes have been fabricated by generation of Au nanoparticle chains, which was produced by reaction between HAuCl4 and sodium citrate without any additional capping agents or surfactants. The self-assembled Au nanoparticles were attached to the surface of glassy carbon electrode (GCE) layer by layer, using L-methionine (L-Met), thiourea (TU), allyl thiourea (ATU) and polyvinylpyrrolidone (PVP) as a crosslinking agent, respectively. The experimental results showed that the electrochemical performance of the different modified electrodes varied in Fe(CN)₆]^3-/4- solution. The Au/L-Met/GCE exhibited an excellent electrochemical property, which is superior to other modified electrodes. In addition, the catalysis of Au/L-Met/GCE to hydrogen peroxide (H₂O₂) also performed a good sensitivity to electrochemical oxidation of H₂O₂ during cyclic voltammetry and chronoamperometry analyses. And the linear range and detection limit for H₂O₂ were 2×10^-7 ~ 3×10^-3 mol·L^-1 and 6.67×10^-8 mol·L^-1, respectively.