Investigation of the Electroreduction Process of Levulinic Acid in Gas Diffusion Electrode with Pb Catalyst by Electrochemical Impedance Spectroscopy

The electrochemical reduction of levulinic acid (LA) on a gas diffusion hydrophobic electrode with a lead (Pb) catalyst has been studied using electrochemical impedance spectroscopy (EIS). The EIS spectra obtained were analyzed using the Warburg impedance model for a finite- length element, and the apparent double- layer capacitance (C-dl) was calculated. The individual contributions of the ohmic, activation, and diffusion components to the resistance of the LA reduction process in 0.5 M H2SO4 were determined. It was found that the capacity of the double layer, charge transfer resistance, and diffusion resistance decrease as the electrode potential increases. An increase in the volume concentration of LA leads to an increase in C-dl and a decrease in both diffusion and activation resistance.