纳米Pt/巯基丁二酰胺铜修饰电极的制备及其电催化活性

Preparaton and Electrocatalytic Activities of Nano Pt/ Dimercaptosuccinic Amide Copper Modified Electrode

利用电沉积法将纳米Pt固定在巯基丁二酰胺铜(II)自组装金电极(Au/CuL)表面,制备了一种纳米催化电极(Au/CuL/nanoPt).分别以扫描电子显微镜(SEM)、原子力显微镜(AFM)、光电子能谱(XPS),表面红外光谱(FT-IR)及电化学交流阻抗(EIS)对电极表面形貌进行了表征,并采用循环伏安法(CV)研究了它的电化学性质.结果表明,CuL具有良好的电化学活性并对H2O2的还原具有电催化作用,纳米Pt可以显著增强这种催化性能.在30℃、0.02mol·L-1PBS缓冲液(pH=6.0)中检测H2O2,在0.00125-0.16mmol·L-1浓度范围呈现线性响应,相关系数为0.9960(信噪比为3),检测极限为0.3μmol·L-1.该电极对H2O2电流响应灵敏度高(0.312mA·cm-2·mmol-1·L)、检测迅速(4.3s)、稳定性好(对46μmol·L-1和2.8mmol·L-1的H2O2连续测10次,变异系数分别为3.1%和3.9%;保存70d后对10μmol·L-1H2O2的响应为初始响应的95%).

Nano Pt/dimercaptosuccinic amide copper （II） （CuL） modified electrode （Au/CuL/nano Pt CME） was prepared by electrodepositing nano crystalline Pt on the surface of CuL monolayer, which was self-assembled on Au electrode （Au/CuL CME）. The electrode′s electrochemical response was studied by cyclic voltammetry （CV） and its surface was characterized by scanning electron micrograph （SEM）, atomic force microscope （AFM）, Fourier transform infrared spectroscopy （FT-IR）, and X-ray photoelectron spectrum （XPS）. The results indicated that the biosensor displayed excellent electrocatalytical response to the reduction of H2O2 in 0.02 mol·L-1 PBS（pH=6.0）. The electrode responsed to H2O2 in the concentration range of 0.00125-0.16 mmol·L-1 with detection limit of 0.3 μmol·L-1 （signal/noise ratio was 3）. Meanwhile, the electrode showed good sensitivity （0.312 mA·cm-2·mmol-1·L in amperometric measurements）, rapid response time （4.3 s）, and reproducibility for long-term use （the variation coefficients were 3.1% and 3.9% （n=10） at 46 μmol·L-1 and 2.8 mmol·L-1 H2O2, respectively; the current maintained 95% for at least more than 70 days to 10 μmol·L-1 H2O2）.