Researchers at Washington University in St. Louis have developed a method to safely power down catalysts that convert waste carbon dioxide into valuable chemicals like acetate. The approach addresses a key problem: renewable electricity from solar or hydro sources is intermittent, and repeatedly turning catalysts on and off degrades them. By keeping the copper cathode at a minimal current density below 1% of normal operation instead of fully shutting it off, the team prevented damage and maintained performance for 750 hours while cutting costs by about 25 percent. The work, published in Nature Catalysis, used spectroscopy and modeling to understand why shutdowns caused copper carbonate buildup or oxidation. The controlled power-down strategy keeps the catalyst in a safe state during price spikes or low renewable generation. The researchers say the next step is to develop more robust catalyst systems for industrial scale carbon monoxide electrolysis. This is a practical step toward making CO2 conversion economically viable when paired with intermittent solar or hydro power.
