Electrochemical reduction of CO 2 on CoNi nanoparticles supported on different carbon matrixes

CoNi nanoparticles were deposited over two different carbon supports. A mesoporous carbon obtained from a resorcinol formaldehyde resin, and commercial carbon nanotubes. The metal nanoparticles were evaluated for the electrochemical reduction of CO ₂ in aqueous media. X-ray diffraction and transmission electron microscopy measurements show differences in the nanoparticle’s morphology. The electrochemical determinations presented different results for the CO2 electroreduction. Formic acid was formed at different potentials on each catalyst as indicated by chromatography. CoNi over mesoporous carbon showed a faradaic efficiency of 32.9% at -0.9 V vs SHE while the metal nanoparticles over nanotubes presented an efficiency of 38.9% at -1.1 V vs SHE. Rotating ring disk electrode determinations also showed different behavior for each metal nanoparticulated catalyst.