That is a question that will depend to an extent on your system however the main challenge associated with CO2 electroreduction is finding a way to lower the overpotential required for reduction (which is very high due in part to the kinetically challenging molecular structural change from linear to bent upon the 1e- reduction) whilst maintaining a reasonable rate of reaction and longevity.

Depending on the product you are looking to attain there are reported catalysts which have addressed some of the issues but as of yet (I think most will agree) the electrochemical reduction is still lacking the necessary efficiency to be considered a viable industrial process.

The diffusivity, as mentioned by Christian, is something which can be resolved by careful experimental design, ( for example gas diffusion electrodes or hydrodynamic techniques) however adsorption of the CO2 or products can lead to lowering activity.

There is an awful lot to read on this topic but I found the reviews by Saveant and Hori to be helpful in understanding the system as well as specific catalysts and existing work.

Good luck!

The CO2 electrochemical reduction is still a kinetic process, using the state of art catalysts. The reduction of CO2 on electrode surface is considered to be sluggish. And multi-step electron/proton transfer is involved.

That is a question that will depend to an extent on your system however the main challenge associated with CO2 electroreduction is finding a way to lower the overpotential required for reduction (which is very high due in part to the kinetically challenging molecular structural change from linear to bent upon the 1e- reduction) whilst maintaining a reasonable rate of reaction and longevity.

Depending on the product you are looking to attain there are reported catalysts which have addressed some of the issues but as of yet (I think most will agree) the electrochemical reduction is still lacking the necessary efficiency to be considered a viable industrial process.

The diffusivity, as mentioned by Christian, is something which can be resolved by careful experimental design, ( for example gas diffusion electrodes or hydrodynamic techniques) however adsorption of the CO2 or products can lead to lowering activity.

There is an awful lot to read on this topic but I found the reviews by Saveant and Hori to be helpful in understanding the system as well as specific catalysts and existing work.

Good luck!