Selective Reduction of Oxygen on Non‐Noble Metal Copper Nanocatalysts

Abstract

Efficient removal of molecular oxygen (O2) from flue gas is necessary to capture and utilize carbon dioxide (CO2) from fossil‐fuel sources. Herein, the catalytic reduction of O2 in simulated flue gases using alumina‐supported copper (Cu) nanostructures is presented. The Cu catalyst outperformed conventional palladium systems for the selectivity toward CO2 over carbon monoxide (CO). Varying the reactant feed ratio can lead to structural rearrangements at the surface of Cu nanoparticles, resulting in significant differences in catalytic activity. Under optimal conditions, a favorable Cu@CuOx core‐shell structure is observed to exhibit both excellent activity and selectivity to CO2. The simulated flue gas is purified from 85% to >99.9% (v/v) CO2 after passing the catalytic system. The catalyst also exhibits high stability, showing only ≈0.1% drop in CO2 after 10 h on stream. This design marks progress toward the sequestration of CO2 and the development of non‐noble catalysts by tuning their dynamic nanostructures under controllable reaction conditions.

CO2coverage on Pd catalysts accelerates oxygen removal in oxy-combustion systems

“…Recent studies have shown their positive progress towards effective O 2 removal. [11][12][13] Supported catalysts using noble metals (e.g., Pd and Pt) and non-noble metals (e.g., Cu) have shown a high removal efficiency of O 2 (495%) at relatively low temperatures (o773 K). [11][12][13] The gas composition in the feed stream has been reported to have a significant consequence on the reactions involving O 2 .…”

“…[11][12][13] Supported catalysts using noble metals (e.g., Pd and Pt) and non-noble metals (e.g., Cu) have shown a high removal efficiency of O 2 (495%) at relatively low temperatures (o773 K). [11][12][13] The gas composition in the feed stream has been reported to have a significant consequence on the reactions involving O 2 . Kuhn et al 12 reported that under O 2 -rich or near stoichiometric conditions (O 2 /CH 4 = 2) in the feed stream, complete CH 4 oxidation was the major reaction.…”

Shape-Controlled Synthesis of Copper Nanocrystals for Plasmonic, Biomedical, and Electrocatalytic Applications

“…Colloidal nanocrystals made of Cu have found widespread use in applications ranging from electronics to optoelectronics, plasmonics, catalysis, sensing, and biomedicine. , For example, Cu nanowires have been demonstrated as a potential replacement for indium–tin oxide (ITO) films in the fabrication of transparent and flexible electrodes, whereas Cu nanoparticles have been widely used as catalysts toward water–gas shift, gas detoxification, and CO 2 sequestration reactions . When prepared as nanostructures, Cu is also known to exhibit localized surface plasmon resonance (LSPR) in the visible and near-infrared regions .…”

“…1,2 For example, Cu nanowires have been demonstrated as a potential replacement for indium−tin oxide (ITO) films in the fabrication of transparent and flexible electrodes, 3 whereas Cu nanoparticles have been widely used as catalysts toward water−gas shift, 4 gas detoxification, 5 reactions. 6 When prepared as nanostructures, Cu is also known to exhibit localized surface plasmon resonance (LSPR) in the visible and near-infrared regions. 7 Recently, Cu-based nanostructures have attracted ever-growing interest owing to their remarkable selectivity toward hydrocarbons and multicarbon (C 2+ ) species during the electrochemical CO 2 reduction reaction (CO 2 RR).…”

Catalytic Removal of Oxygen Impurities from Pressurized Oxy-Combustion Flue Gas for the Production of High-Purity Carbon Dioxide

“…The addition of a reducing gas, such as hydrogen (H 2 ), carbon monoxide (CO), and methane (CH 4 ) at stoichiometric ratios with O 2 , has been effective in removing O 2 to below 1000 ppm. However, H 2 is more expensive and may react with CO 2 via the reverse water gas shift reaction, and CO for O 2 reduction demands narrow specifications for both CO and O 2 . , Therefore, CH 4 is a preferred choice of reductant because of both economic and technical considerations. In another recent study, catalytic reduction of O 2 from flue gas with noble metals has also been reported, but the work has little relevance to pressurized flue gas .…”