Novel Eco-Friendly Electrode: Copper Nanoparticle-Doped MWCNTs for Green Electro-Organic Synthesis of 1,2,3-Triazoles With ChCl/Urea as a Solvent and Cocatalyst

Abstract

Meticulous electrode design is pivotal in advancing greener and more sustainable electro-organic synthesis practices. In this research, our team designed and synthesized a copper-doped electrode on multiwalled carbon nanotubes (MWCNTs) and characterized it using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) analysis, X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) analysis. Subsequently, this electrode was utilized as a catalyst at the electrode surface, serving as a cathode in electro-oxidation reactions in the presence of phenylacetylene, sodium azide (NaN₃), and benzyl halide for the production of 1,2,3-triazole derivatives under ambient temperature, within a 30-min reaction time, and at atmospheric pressure, achieving an efficiency level ranging from good to excellent, specifically between 88% and 96%. The synthesized 1,2,3-triazole derivatives were identified using proton nuclear magnetic resonance (¹H NMR) spectroscopy, CHN elemental analysis, and melting point. In this paper, choline chloride/urea deep eutectic solvents (DES) serve multiple roles in the reaction mechanism. They function as solvents and co-catalysts, generate weak bases, and provide numerous advantages in green chemistry. These advantages include low toxicity, reduced environmental risks, improved atom economy, and non-volatility, making them safer alternatives to traditional organic solvents.