| Introducing Schiff Base Network1 COF as a Novel Electrocatalytic Modifier for the Development of New Electrochemical Sensors: DFT and Experimental Studies |
| کد مقاله : 1020-CNF |
| نویسندگان: |
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محمدرضا جلالی سروستانی *1، طیبه مدرکیان2، عباس افخمی1 1گروه شیمی تجزیه، دانشکده شیمی، دانشگاه بوعلی سینا، همدان، ایران 2گروه شیمی تجزیه، دانشکده شیمی، دانشگاه بوعلی سینا، همدان ایران |
| چکیده مقاله: |
| In this study, the performance of a recently synthesized covalent organic framework (Schiff base network1 (SNW1)) as a new electrocatalytic modifier was investigated by electrochemical impedance spectroscopy, cyclic voltammetry and frontier molecular orbital (FMO) computations. For this purpose, SNW1 was synthesized and characterized by FT-IR, SEM and EDS techniques. Afterward, a glassy carbon electrode was modified by drop-casting with a 2mg/ml dispersed solution of SNW1 and then, the cyclic voltammograms and electrochemical impedance spectrums of the bare and modified electrodes in the K4Fe(CN)6 as the probe was recorded. The obtained results showed the potential discrepancy between the cathodic and anodic peak currents in the cyclic voltammograms declined remarkably from 0.4 V to 0.13 V after modification process. Besides, both anodic and cathodic peak current experienced a sharp enhancement (2.2 folds in comparison to the bare GCE) and the Nyquist plots demonstrate the electron transfer resistance (Rct) has reduced from 458.6 to 204.0. All of the results indicated that SNW1 has acceptable conductivity and great electrocatalytic behavior. Therefore, it can be employed as a novel modifier for the fabrication of electrochemical sensors. In order to check out the function of SNW1 as an electrocatalytic modifier, its structure was drawn in the GuassView 16 software and two heavy metal ions (Hg2+ and Pb2+) as the model analytes was inserted near the COF from four different orientations. Then, geometrical optimization and FMO computations were implemented on the designed structures. The calculated negative adsorption energies (Eads) showed the adsorption of both cations are experimentally feasible and the interaction of SNW1 with Hg2+ and Pb2+ are thermodynamically favorable. The computed density of state (DOS) spectrums showed the bandgap of SNW1 has experienced a tangible decrease (at least 5.0 (eV)) in the adsorption process of both cations which proved the electrochemical conductivity of the studied COF has improved significantly after the adsorption of Hg2+ and Pb2+ cations. Hence, it can be concluded that SNW1 is a promising electrocatalytic modifier for the development of a new electrochemical sensor for the determination of Hg2+ and Pb2+. |
| کلیدواژه ها: |
| Covalent organic framework, Electrochemical sensor, DFT, Electrochemical impedance spectroscopy, Cyclic voltammetry |
| وضعیت : چکیده برای ارائه به صورت پوستر پذیرفته شده است |