Highly efficient electro-oxidative synthesis of sulfoxides: synergistic effect of an optimized copper(ii) complex and...

Integrating molecular catalysts with conductive supports is a proven strategy to enhance the kinetics of electro-catalytic processes. In this study, we developed a high-performance heterogeneous electro-catalyst, the FET-Cu-GO hybrid, specifically designed for the electro-oxidative synthesis of sulfoxides. By using TBTU as a coupling agent, we covalently anchored a copper(ii)-Schiff base complex onto a functionalized graphene oxide (GO) matrix. This approach created a stable interface that effectively prevents metal leaching and ensures rapid charge-transfer. To ensure absolute structural precision, the coordination geometry and The molecular architecture of the active site were determined by single-crystal X-ray diffraction. The synthesis and stabilization of the hybrid catalyst were further confirmed through a comprehensive set of analyses, including FT-IR, UV-vis, SEM, TEM, TGA, AAS, EDX, and powder XRD. Additionally, the electrochemical behavior and charge-transfer kinetics were analyzed via Cyclic Voltammetry (CV) and Chronoamperometry (CA), confirming both the stability of the active sites and the efficiency of the support. Commitment to the principles of green chemistry was central to this work; we employed hydrogen peroxide (H₂O₂) as a benign green oxidant and ethanol as a sustainable solvent, eliminating the need for toxic additives. When tested at an applied potential of 55 V, the system achieved 100% conversion and total selectivity in only 78 seconds. Notably, the catalyst exhibited exceptional recyclability over six consecutive cycles with no detectable metal leaching, underscored by a remarkable turnover number (TON) of 46 000. Overall, this work bridges the gap between the precision of molecular catalysts and the durability required for industrial applications, offering a promising blueprint for sustainable, high-throughput organic transformations.