Converting CO₂ to CO

Here’s an interesting technology. nanotechweb.org reports that researchers have found a way to convert carbon dioxide to carbon monoxide, a useful precursor to hydrocarbons useful as fuel, using available energy and cheap catalysts:

Researchers in Switzerland and Spain have developed a solar-driven electrolyser that converts CO2 to CO using only Earth-abundant elements in place of precious metals. Reducing emissions of CO2 by converting it electrochemically to CO is an attractive prospect due to the potential use of CO as a precursor to fuels and high-value chemicals. The work leads the way to further exploration of Earth-abundant metals that might perform comparably to the rare elements used until now.

The conventional method to convert CO2 to CO uses precious-metal catalysts (gold, silver, palladium) at considerable overpotentials and also requires electrolyte additives. What this research has demonstrated is an innovative, inexpensive and stable alternative using a bifunctional system of SnO2-modified CuO electrodes separated by a bipolar membrane and driven by a solar cell. This newly developed system constitutes a milestone for the catalysis community as it avoids the requirement – until now – of noble metals.

There’s lots of work remaining before a viable product emerges, of course. For one thing the technology must be scaleable. Something that works in the lab isn’t the same thing as something that will work in production. But it’s still an interesting technology.