Extraction-driven copper-complex for electrochemical oxidation of PFOA on portable electrodes
MICROCHEMICAL JOURNAL, cilt.218, 2025 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 218
- Basım Tarihi: 2025
- Doi Numarası: 10.1016/j.microc.2025.115797
- Dergi Adı: MICROCHEMICAL JOURNAL
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, Chimica, Index Islamicus
- İstanbul Üniversitesi-Cerrahpaşa Adresli: Evet
Özet
Perfluorooctanoic acid (PFOA), a legacy per- and polyfluoroalkyl substance, resists natural attenuation and is now regulated at single-ppb levels in drinking water. Rapid, field-deployable quantification is, therefore, essential for evidence-based remediation. Here we report a flexible screen-printed sensor that employs a molecular-scale, copper imidazolyl-pyridine complex synthesized in a single room-temperature extraction step. The N-chelated Cu center exhibits a Cu2+/Cu+ redox couple that oxidizes the carboxylate PFOA at -0.42 V, well within the aqueous window. Differential-pulse voltammetry exhibits linearity from 0.05 to 5.20 mu M (LOD = 0.74 mu M), whereas amperometry achieves a detection limit of 24.0 pM with a 3.8 s time constant, meeting the requirements for on-site monitoring. DFT calculations reveal that complexation compresses the frontier orbital gap, aligns the Cu 3d acceptor states with the PFOA carboxylate donor level, and affords a Cu-O coordination energy of approximately -23 kcal & sdot;mol- 1, as determined by QTAIM analysis, which favors rapid yet reversible adsorption. Molecular-dynamics trajectories confirm the stability of a vertically oriented adduct, and an artificial neural network model predicts concentration from raw voltammograms with an R2 value of 0.99 (mean absolute error, MAE, of 0.24), enabling calibration-free readout. By uniting green synthesis, metal-centered catalysis, and data-intelligent signal processing, this work delivers a practical, low-cost platform for high-frequency PFOA surveillance and provides a template for extending molecular Cu electrocatalysts to the broader PFAS family.