Biomimetic CO oxidation below-100 °C by a nitrate-containing metal-free microporous system

CO oxidation is of importance both for inorganic and living systems. Transition and precious metals supported on various materials can oxidize CO to CO2. Among them, few systems, such as Au/TiO2, can perform CO oxidation at temperatures as low as -70 degrees C. Living (an)aerobic organisms perform CO oxidation with nitrate using complex enzymes under ambient temperatures representing an essential pathway for life, which enables respiration in the absence of oxygen and leads to carbonate mineral formation. Herein, we report that CO can be oxidized to CO2 by nitrate at -140 degrees C within an inorganic, nonmetallic zeolitic system. The transformation of NOx and CO species in zeolite as well as the origin of this unique activity is clarified using a joint spectroscopic and computational approach. CO oxidation is of importance both for inorganic and living systems. Here the authors demonstrate that CO can be oxidized by nitrate in small-pore SSZ-13 zeolite at a temperature below -100 degrees C using spectroscopy and density functional theory calculations.

Automated summary

CO oxidation is important for both inorganic and living systems. Transition and precious metals can oxidize CO to CO2 on various materials, while aerobic organisms perform CO oxidation with nitrate using complex enzymes at ambient temperatures. Nitrate can facilitate CO oxidation, leading to the transformation of NOx and CO species in zeolite systems.