Selective Heterogeneous CO₂ Electroreduction\nto Methanol

Abstract

Catalytic electroreduction of carbon\ndioxide to useful chemical\nfeedstocks is an environmentally and technologically important process,\nyet the low energy efficiency and difficulty in controlling product\nselectivity are great challenges. The reason for part of the latter\nis that there are presently no catalyst design principles to selectively\ncontrol CO₂ electroreduction toward a desired product.\nIn this work, as a first attempt, we suggest combining a few criteria\n(CO binding energy, OH binding energy, and H binding energy) that\ncan be collectively used as activity- and selectivity-determining\ndescriptors to preferentially produce methanol over methane from CO₂ electroreduction. We then apply these concepts to near-surface\nalloys (NSAs) to propose efficient and selective CO₂ electrochemical\nreduction catalysts to produce methanol. The W/Au alloy is identified\nas a promising candidate to have increased catalyst efficiency (decreased\nCO₂ reduction overpotential and increased overpotential\nfor unwanted hydrogen evolution) as well as improved product selectivity\ntoward methanol, in comparison to conventional Cu catalyst.