检出限
材料科学
电化学
电极
介电谱
电化学气体传感器
电子转移
循环伏安法
分析化学(期刊)
阳极溶出伏安法
选择性
金属有机骨架
无机化学
化学
色谱法
物理化学
有机化学
催化作用
吸附
作者
Sherman Lesly Zambou Jiokeng,Tobie J. Matemb Ma Ntep,Marcus N. A. Fetzer,Till Strothmann,Cyrille Ghislain Fotsop,Ignas Kenfack Tonlé,Christoph Janiak
标识
DOI:10.1021/acsami.3c15931
摘要
As the excessive presence of heavy metals in the environment significantly affects human health, it becomes necessary to develop efficient, selective, and sensitive methods for their detection. In this study, a novel electrochemical sensor for the detection of Pb2+ ions is described. The proposed sensor is based on a glassy carbon electrode (GCE) modified by a thin film of histidine-grafted metal–organic framework (MOF-808-His). The MOF-808 was obtained solvothermally, and then postsynthetically modified by substituting the coordinated acetate with histidinate. By electrochemistry, the MOF-808-His-modified GCE demonstrated high charge selectivity, while electrochemical impedance spectroscopy (EIS) and kinetic studies gave a lower charge transfer resistance (4196 Ω) and a better standard heterogeneous electron transfer rate constant (1.80 × 10–5 cm s–1) on MOF-808-modified GCE. These results indicated a swift and direct electron transfer rate from [Fe(CN)6]3–/4– to the electrode surface. Using square wave anodic stripping voltammetry (SWASV), the rapid and highly sensitive determination of Pb2+ was achieved on MOF-808-His-modified GCE. By optimizing the accumulation-detection parameters including pH of the detection medium, deposition time and potential, and concentration, a remarkable limit of detection (LoD, based on a signal-to-noise ratio of 3) of (1.12 × 10–10 ± 0.10 × 10–10) mol L–1 was obtained, with a sensitivity of (9.6 ± 0.1) μA L μmol–1. After interference and stability studies, the MOF-808-His-modified GCE was applied to the detection of Pb2+ in a tap water sample with a concentration of 10 μmol L–1 Pb2+.
科研通智能强力驱动
Strongly Powered by AbleSci AI