The formation of FNR@FeOx core-shell nanoparticles on SFMNR electrodes led to a significant decrease in polarization resistance (Rp) from 6.9 Ω cm² to 1.9 Ω cm² at 750°C, and a sharp reduction in activation energy from 2.1 eV to 0.82 eV (Figure ). This reduction in resistance, particularly in the middle-to-high frequency ranges, is further confirmed by distribution of relaxation time (DRT) analysis (Figure ), which indicates that the formation of FNR@FeOx core-shell nanoparticles enhance the surface-related CO2 dissociation reaction. CO2-temperature-programmed desorption (TPD) results indicate that the formation of FNR@FeOx coreshell nanoparticles on SFMNR facilitates CO2 exchange and provides more CO2 adsorption sites on the surface, as can be seen by the enlarged CO2 desorption area. The SFM sample shows two major desorption peaks at 616 °C and 768 °C. Partial substitution of Mo with Ni and Ru in SFM shifts these peaks to lower temperatures (470 °C and 671 °C), with the latter being dominant. In the presence of FNR@FeOx core-shell nanoparticles, the major desorption peak further shifts to 595°C. The moderate CO2 adsorption on FNR@FeOx core-shell nanoparticles may facilitate CO2 exchange at around 600°C, potentially enhancing reaction kinetics.