Mechanochemical Synthesis and Characterization of Nano-oxides for the Electrochemical Reduction of CO₂

In recent decades, the electrochemical conversion of carbon dioxide (CO₂) has attracted considerable scientific and technological interest, and it is a valid alternative for overcoming the intrinsic limits of traditional industrial approaches. This technology reduces the number of process steps, works under milder conditions, and allows the direct valorization of CO₂. This thesis focuses on the synthesis of electrocatalysts based on nanomaterials containing copper (Cu) and silver (Ag) for the electrochemical CO₂ reduction reaction (CO₂RR). The main aim of the research is to evaluate which nanomaterial compositions are the most functional and selective in promoting the conversion of CO₂ into high-value products. The nanomaterials were synthesized by mechanochemical methods: ball milling or manual grinding in a mortar. They were then deposited on a conductive carbon substrate (carbon paper) with a geometric area of 1 cm². A preliminary electrochemical characterization was carried out by cyclic voltammetry (CV) to investigate the redox processes of the material. In addition, the structural and morphological properties of the deposited catalysts were carefully examined by X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS), and Raman spectroscopy. The electrocatalytic performance was evaluated by chronoamperometric tests at controlled potential, while the liquid reaction products were identified and quantified by proton nuclear magnetic resonance spectroscopy (¹H-NMR).