Studies on the Electrochemical Behaviors of Caffeic Acid with Carbon Black/Carbon Quantum Dot/Metal Organic Frameworks Modified Glassy Carbon Electrode
| Autor: | KUO, JIN-PING, 郭進平 |
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| Rok vydání: | 2019 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 107 In this study, using nano carbon black/carbon quantum dot (CQD)/metal-organic frameworks (MOFs) modified electrode detecting caffeic acid, and investigating the electrochemical properties of the modified electrode. The metal organic frameworks have been successfully scrutinized by using Fourier transform infrared spectroscopy (FT-IR) and powder X-ray diffraction (PXRD), transmission electron microscopy (TEM) and fluorescence spectrometer successful identify the CQD, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) confirmed that carbon black/carbon quantum dots/metal-organic frameworks modified electrode can be successfully prepared. In these optimal conditions, differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) were used to confirm nano carbon black/carbon quantum dots/metal-organic frameworks modified electrode has excellent electron transfer characteristics, low electron transfer resistance and increase oxidation current signal characteristics. After the optimization process, the electrochemical detection of CA in a wide concentration range, from 0.1 μM to 20 μM concentration range, with the limit of detection (S/N = 3) of 20 nM. In addition, the repeatability of the CB/CQD/MOFs/GCE was measured in the intra-day and inter-day and the relative standard deviation (RSD) was less than 6.93 % and 1.15 %, respectively. Stability remained above 94.52 % after 20 scan by DPV, long-term stability remained above 84.78 %, which confirmed that the modified electrode has good repeatability and stability. Finally, CB/CQD/MOFs/GCE applied in determination of caffeic acid in commercial beverages. The recovery was between 95.01 to 113.14 %, which shows the feasible detection of CA in real sample. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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