Redox-active N,O-chelating Schiff base complexes of Ni(ii), Ag(i) and Ru(ii) as molecular electrocatalysts for water splitting
New Journal of Chemistry, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1039/d6nj02513g
- Dergi Adı: New Journal of Chemistry
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, EMBASE, DIALNET, Academic Search Ultimate (EBSCO), Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Erciyes Üniversitesi Adresli: Evet
Özet
Developing efficient electrocatalysts for the oxygen evolution reaction (OER) is critical for advancing sustainable energy technologies. Herein, a Schiff base ligand (SB) and its Ni(ii), Ag(i) and Ru(iii) complexes were synthesized and characterized through mass spectrometry and UV-Visible, Fourier transform infrared (FTIR), Raman and nuclear magnetic resonance (NMR) spectroscopies, while surface morphology was evaluated through powder X-ray diffraction (PXRD) and scanning electron microscopy coupled with energy-dispersive X-ray (SEM-EDX/EDS) studies. The OER performance of the synthesized catalysts was evaluated using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) and double-layer capacitance (Cdl), electrochemical surface area (ECSA) and redox analyses. Among the studied catalysts, Ru-SB exhibited the highest catalytic activity, with a lower overpotential (η = 134.6 mV, E = 1.3646 V vs. RHE) than those of Ag-SB (205.6 mV), Ni-SB (522.2 mV) and SB (539.9 mV). Tafel slopes followed the trend of Ru-SB (31.4 mV dec−1) < Ag-SB (77.3 mV dec−1) < Ni-SB (92.2 mV dec−1) < SB (96.7 mV dec−1), indicating faster kinetics for Ru-SB. EIS analysis revealed lower charge-transfer resistance for Ru-SB and Ag-SB. Higher Cdl (504.5 µF) and ECSA (12.61 cm2) values for Ru-SB further confirmed its larger electroactive surface area. Redox studies showed that Ru-SB accesses the key pre-OER oxidized state at the lowest potential (0.6931 V), correlating with its superior activity, while SB lacks metal-centered redox flexibility. Overall, the results highlight the decisive role of the metal center, with Ru-SB emerging as a highly efficient OER electrocatalyst that can be further studied for commercial applications.