Capture of CO2 and conversion into useful chemicals can alleviate atmospheric buildup and provide an alternative source of chemical building blocks. CO₂ can be reduced electrochemically to small chain carbon molecules (C1-C3) like CO, ethylene, formic acid, methane and alcohols.¹ Integrating multiple catalytic sites on an electrode surface enables further reduction to higher value hydrocarbons.

In this work, we describe kinetic Monte Carlo (kMC) simulations of CO₂ reduction to ethane on an integrated catalytic electrode surface. Electrode surface incorporates two catalyst sites, which may include molecular catalytic structures or tethered metal complexes.² The catalytic mechanism at each active site, as well as adsorption and transport of intermediates between sites, is considered in the overall model. Monte Carlo simulation allows inclusion of both kinetic and transport events whose time scales span multiple orders of magnitude.³ Channeling of intermediate transport between active sites via Van Der Waals, electrostatic, and ligand-exchange interactions is considered. We predict the effect of catalyst loading and composition on overall cascade efficiency, a defined by ethane yield.

References

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2. A. S. Varela, N. Ranjbar Sahraie, J. Steinberg, W. Ju, H.-S. Oh, and P. Strasser, Angew. Chemie Int. Ed., 54, 10758–10762 (2015) doi:10.1002/anie.201502099.
3. M. Stamatakis and D. G. Vlachos, ACS Catal., 2, 2648–2663 (2012) doi:10.1021/cs3005709.