负载金纳米颗粒的Ag-MOFs合成及其在过氧化氢检测中的应用

Synthesis of gold nanoparticle loaded Ag-MOFs and its application in detection of hydrogen peroxide

电化学传感方法检测H2O2含量具有很多优点,已有很多文献报道。然而,受纳米材料形貌、传感界面构建方法等因素的影响,其灵敏度和检出限有待进一步提高。实验通过水热法合成了银-对苯二甲酸金属-有机骨架纳米复合材料(Ag-MOFs),为提高传感器的分析性能,又将金纳米颗粒(AuNPs)负载于Ag-MOFs表面,合成了AuNPs/Ag-MOFs,从而构建了一种新颖的无酶H2O2电化学传感器。使用透射电镜表征,发现Ag-MOFs呈棒状,长400~600nm。通过循环伏安法、安培法等电化学方法测定了电化学传感器的性能。所构建的电化学传感器对H2O2的还原具有优异的催化性能,催化电流与H2O2浓度在0.6μmol/L^18.5mmol/L呈线性关系,灵敏度高达219.5μA·(mmol/L)-1·cm-2,检出限为0.3μmol/L(S/N=3)。选择3个消毒剂样品,实验前,首先稀释样品溶液,再采用电化学传感器测定了其中H2O2浓度,结果的相对标准偏差(RSD,n=6)小于4%;且与KMnO4滴定法测定结果基本一致。

The detection of H2O2 content by electrochemical sensor method has many advantages and there have been many reports.However,the sensitivity and the limit of detection should be further improved because they are affected by the morphology of nanomaterials and the construction method of sensing interface.The silver(I)-terephthalate metal-organic frameworks(Ag-MOFs)were synthesized by the hydrothermal method.In order to improve the analytical performance of sensor,the gold nanoparticles(AuNPs)were loaded on the surface of Ag-MOFs,AuNPs/Ag-MOFs were synthesized,thus a novel enzyme-free H2O2 electrochemical sensor was constructed.The transmission electron microscope(TEM)characterizations indicated that Ag-MOFs were rod-shaped with length of 400-600 nm.The performance of electrochemical sensor was measured by the electrochemical methods including cyclic voltammetry and amperometry.It was found that the constructed electrochemical sensor exhibited excellent catalytic performance on the reduction of H2O2.The catalytic current was linear to the concentration of H2O2 in range of 0.6μmol/L to18.5 mmol/L.The sensitivity was up to 219.5μA·(mmol/L)-1·cm-2 and the limit of detection was 0.3μmol/L(S/N=3).Three disinfectant samples were tested.The sample solution was firstly diluted before experiments.Then the concentration of H2O2 was determined by electrochemical sensor.The relative standard deviations(RSD,n=6)of results were less than 4%.The found results were basically consistent with those obtained by KMnO4 titration method.