Author: BIRUTĖ SERAPINIENĖ
Dissertation title: Electrocatalytic activity of Cu electrodes in electroreduction of CO2
Fields of science: Chemistry N 003
Scientific supervisor: Prof. Habil. Dr. Rimantas Ramanauskas
Defence of the dissertation: 24 October 2025
SUMMARY: Copper has a unique ability to convert carbon dioxide into hydrocarbons with significant Faradaic efficiency. The main objective of this study was to evaluate the structure-property relationship of 3D copper foam electrodes in the electrochemical reduction of carbon dioxide to hydrocarbons containing two carbon atoms. A suitable method for evaluating the electrochemically active surface area of highly porous copper electrodes was determined. The influence of different additives in the copper electrode deposition solution on the electrochemically active surface area and mechanical properties was evaluated. The microstructure of the copper 3D electrodes, deposited from solutions with different compositions, enabled the structure-property relationship for the electrochemical reduction of carbon dioxide to be established. The deposited samples were characterised using SEM and electrochemical techniques, including Pb underpotential deposition, to determine the contribution of crystal facets. It was found that, to achieve maximum yields of compounds containing two carbon atoms during the electrochemical reduction of carbon dioxide, copper 3D electrodes should be deposited in additive-free electrolytes with surface roughness coefficients of up to ~800. Furthermore, the yields of two-carbon-atom compounds formed during carbon dioxide electrochemical reduction are determined by the shape, size and spatial arrangement of crystallite aggregates within the copper 3D structure.