Energy- and carbon-efficient CO2/CO electrolysis to multicarbon products via asymmetric ion migration–adsorption

Localized Alkaline Environment via In Situ Electrostatic Confinement for Enhanced CO2-to-Ethylene Conversion in Neutral Medium

“…27 However, further increasing the cation concentration has a negative effect on ethylene FE on Cu/PTFE, likely due to the aggravated formation of carbonate salts. The influence of the cation concentration on carbon/Cu/PTFE was not obvious, where the carbon layer may limit the migration of K + ions to the interface and prevent harmful carbonate formations 45 (Figure S15b). Although slightly different Cu surface morphologies were observed after electrochemical tests for carbon/Cu/PTFE (carbon layer removed by N-methyl-2-pyrrolidone) and Cu/PTFE, they do not show noticeable differences in ethylene selectivity (Figure S16c).…”

Hydrophobic, Ultrastable Cuδ+ for Robust CO2 Electroreduction to C2 Products at Ampere-Current Levels

“…We analyzed the liquid products in the anolyte to detect liquid products that may have crossed over the membrane. 9 The current−voltage response for the Cu CF catalyst with a constant CO 2 flow is shown in Figure S27. The selectivity and total current for C 2 products both increased with the increasing operating cell voltage from −2.1 to −2.7 V. The Cu CF catalyst displayed the maximum FE for C 2 products at 90.4% at −2.7 V with a large partial current density of 341.6 mA cm −2 at −2.8 V (Figure 2e).…”

“…The as-synthesized liquid products at the cathode were collected by using a cold trap connected to the cathode gas outlet (Figure S26). We analyzed the liquid products in the anolyte to detect liquid products that may have crossed over the membrane . The current–voltage response for the Cu CF catalyst with a constant CO 2 flow is shown in Figure S27.…”

“…Electroreduction of carbon dioxide (CO 2 RR) to value-added products using renewable energy offers a feasible pathway to realize carbon-neutral energy cycle. , Among various CO 2 RR products, multicarbon (C 2+ ) products, such as C 2 H 4 , C 2 H 5 OH, and CH 3 COOH, have attracted wide attention due to their high energy densities. − Efficient CO 2 -to-C 2+ convention involves multiple proton-coupled electron transfer processes, which accompanied with multiple intermediates on catalytic sites often lead to a low activity and selectivity. Therefore, it is important and challenging to develop effective electrocatalysts for CO 2 RR. , Copper (Cu) materials showed great promise to promote selective electroreduction of CO 2 to C 2+ products with a high conversion efficiency. − Recent studies have demonstrated that the moderate oxidation state of Cu (Cu δ+ ) played a critical role in steering the CO 2 RR pathway toward the high-efficacy C 2+ formation. − However, Cu δ+ active sites are extremely unstable during CO 2 RR, and various strategies, including plasma treatment, heteroatom doping, and organic molecular modification, have been explored to stabilize Cu δ+ . ,,− Recent advances have improved the Faradaic efficiency (FE) toward C 2+ products up to around 80 to 90%. ,− In spite of these efforts, Cu δ+ sites still suffer from the in situ self-reduction during CO 2 RR. This makes it very difficult to maintain a high CO 2 RR activity, especially at high operating current densities …”

Electrochemical wastewater refining: a vision for circular chemical manufacturing

“…At the microscale, separations can mediate reactant and product transport between bulk electrolytes and interfacial microenvironments. 86 In turn, changes in microenvironments, such as basification observed during NO3RR, can influence catalytic activity and selectivity. At the macroscale, integrated reactive separation processes can leverage membrane-separated cell architectures to control electrolyte composition amidst variable influent wastewater compositions.…”