| Development of a Chromium(III)-Selective Carbon Paste Electrode Based on a Novel Selenourea Derivative Ionophore: Experimental and Computational Investigation |
| کد مقاله : 1704-IWWA |
| نویسندگان |
|
حانیه دمرچلی *، لیلا حاجی آقابابایی، اشرف سادات شاه ولایتی، جمشید نجف پور مرکز تحقیقات فناوری های نوین در شیمی و علوم وابسته دانشگاه آزاد اسلامی واحد یادگار امام خمینی(ره) |
| چکیده مقاله |
| A novel Cr(III)-selective carbon paste electrode was developed using N-((4-methoxybenzyl)carbamoselenoyl)-4-methylbenzamide as a neutral ionophore, which was synthesized, characterized by FTIR, ¹H NMR and ¹³C NMR, and applied for the first time in potentiometric sensing. Density functional theory calculations at the B3LYP/6-311+G(d,p) level were performed to evaluate the electronic structure and complexation thermodynamics of the ionophore with fifteen metal cations in both gas and aqueous phases. Cr³⁺ exhibited the most negative Gibbs free energy of complexation in both media, supporting the preferential affinity of the ionophore toward Cr(III). The carbon paste composition was optimized, and the electrode containing 12% ionophore, 63% graphite powder and 25% paraffin oil exhibited a near-Nernstian slope of 19.59 mV decade⁻¹ over the linear concentration range of 7 × 10⁻³ to 3 × 10⁻⁷ mol L⁻¹, with a detection limit of 2.1 × 10⁻⁷ mol L⁻¹. The proposed sensor showed a fast response time of approximately 5–6 s and stable potentiometric behavior within the pH range of 4–7. Selectivity coefficients evaluated by the matched potential method revealed a preferential response toward Cr³⁺ over the investigated interfering cations, with the highest interference observed for Ni²⁺ and Pb²⁺. The developed electrode offers a simple, low-cost and rapid analytical tool for the determination of Cr(III) in aqueous samples, and its analytical performance was assessed according to IUPAC recommendations. |
| کلیدواژه ها |
| Cr(III)-selective electrode, Selenourea ionophore, Carbon paste electrode, Potentiometry, DFT calculations, Water analysis |
| وضعیت: پذیرفته شده برای ارسال فایل های ارائه پوستر |
