A Raman spectroscopic study of the carbon deposition mechanism on Ni/CGO electrodes during CO/CO2 electrolysis.

In situ and ex situ Raman analyses of porous Ni/CGO electrodes reveal differences in the amount, location and type of carbon formed during CO/CO2 electrolysis. The results demonstrate the limitations of optical in situ techniques applied to Solid Oxide Cells (SOCs) operated in electrolysis conditions. Increased carbon deposition close to the electrode-electrolyte interface is likely to be the result of high charge-transfer current in that area. The positive effect of a CGO interlayer on reducing carbon formation on the fuel electrode is demonstrated.