Electrocatalytic Upgrade of Impure CO₂ by In Situ-Reconstructed Cu Catalysts with Gas Exsolution Electrolyzers

Abstract

Electrochemical upgrading of CO 2 to multicarbon chemicals is widely investigated for carbon neutrality, while the activity of catalysts and the production rate of electrolyzers require further improvements to satisfy industrial demands, especially with impure CO 2 at a low concentration. We propose to employ in situ electrodeposition of Cu on different substrates to improve the activity and selectivity of catalysts and further assemble the electrodes into a customized flow-through electrolyzer to boost the conversion rate. The Cu catalyst on a carbon fabric (CF) substrate demonstrates the highest current density among the controlled samples. This is ascribed to the promoted in situ CO 2 exsolution for carbon supply induced by a CF substrate with interlaced fibers, as proved by the combined porescale multiphysics simulation and experimental characterizations. Therefore, Cu catalyst on the CF substrate shows Faradaic efficiency of over 90% for the total carbon products and a current density of over 300 mA•cm −2 at −0.83 V versus RHE. Furthermore, such a customized flow-through cell using an aqueous electrolyte demonstrates a stable and efficient upgrade of CO 2 with both pure and impure CO 2 (90%) inlets, exhibiting auspicious prospects for the industrial application of CO 2 electrolysis.

Ni-Decorated N-Doped Biomass-Derived Porous Carbon toward Efficient Electroreduction of CO2 to CO

“…Nowadays, the widespread use of chemical fuels has caused the atmospheric concentration of carbon dioxide (CO 2 ) to rise quickly, causing global warming issues. − Therefore, the conversion of CO 2 into useful carbon-based products is urgently needed, which is important for realizing a carbon-neutral cycle. , In recent years, the electrochemical CO 2 reduction reaction (CO 2 RR) has caught the eye of widespread researchers . The CO 2 RR could deplete CO 2 while producing high-added-value carbon products, such as CO, CH 4 , HCOOH and CH 3 OH. , However, CO 2 RR usually exhibits poor catalytic selectivity and low energy conversion efficiency because of the strong CO bond, the low electron affinity, and the competitive hydrogen evolution reaction (HER). , Carbon monoxide (CO), as a CO 2 RR product, is an important chemical feedstock for some synthetic reactions, such as Fischer–Tropsch synthesis and oxalic acid synthesis . In addition, efficient and highly selective catalysts are indispensable in the CO 2 RR.…”