Advanced Cu-Sn foam for selectively converting CO2 to CO in aqueous solution

• Published in: Applied catalysis. B, Environmental Environmental, 2018-11, Vol.236, p.475-482
• Main Authors: Zeng, Juqin, Bejtka, Katarzyna, Ju, Wenbo, Castellino, Micaela, Chiodoni, Angelica, Sacco, Adriano, Farkhondehfal, M. Amin, Hernández, Simelys, Rentsch, Daniel, Battaglia, Corsin, Pirri, Candido F.
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Catalyst; Copper-tin foam; Dendrite structure; Electrochemical reduction
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2018.05.056

[Display omitted] •A Sn-modified copper foam is simply prepared by electrodeposition.•In the coral-like foam, each dendrite has a Cu core and a CuOx/SnOx shell.•CO faradaic efficiencies over 90% are obtained from -0.6 V to -1.0 V vs. RHE.•High current densities for CO are observed at moderate-to-high overpotentials.•The Cu-Sn foam shows high stability during the CO2 electrolysis. A tin-modified copper foam for the efficient and selective reduction of CO2 to CO is reported. We employ a cost-efficient electrodeposition route to form a three-dimensional porous dendrite architecture, in which each dendrite possesses a copper core and a copper oxide/tin oxide shell. The sparse tin species on the electrode surface play a key role to achieve excellent faradaic efficiencies for CO formation with a maximum value of 94%. We demonstrate high CO partial current densities of 4.7 mA cm−2 and 7.9 mA cm−2 at applied potentials of -0.8 V and -1.1 V vs. the reversible hydrogen electrode, respectively. The high activity for electrochemical CO2 reduction is attributed to the unique hierarchical porous structure, which offers abundant electrochemically active sites and facilitates mass transport.