Electrochemical Control of the Morphology and Functional Properties of Hierarchically Structured, Dendritic Cu Surfaces

by Mehrabi, H.; Conlin, S. K.; Hollis, T. I.; Gattis, B. S.; Weker, J. N.; Coridan, R. H.

Electrodeposited dendritic copper foams have been extensively studied as an electrocatalyst for CO2 reduction reaction (CO2RR). Many parameters, such as dendrite size, porosity, pore size, and crystal faceting, define the hierarchical properties of these structures and their subsequent bubble evolution and CO2RR capabilities. Herein, the effects the electrodeposition conditions (potential, pH) have on the resulting crystallinity, microstructure, and macroporosity of the copper foam are studied. These morphological differences and the corresponding effects on electrocatalytic activity are characterized. It is shown that the composition of the electrodeposition bath can have significant effects on the mechanics of bubble formation and detachment at the surface during hydrogen evolution reaction in acidic solutions. Similarly, the electrodeposition conditions for the synthesis of the foam affect the product selectivity during CO2RR electrocatalysis. Foams deposited in alkaline electrodeposition solutions show high faradaic efficiency and specificity toward C2H6, an uncommon product of CO2RR, at modest applied potentials (-0.8 V versus reversible hydrogen electrode.

Journal
Energy Technology
Volume
11
Issue
3
Year
2023
URL
https://dx.doi.org/10.1002/ente.202201124
ISBN/ISSN
2194-4288
DOI
10.1002/ente.202201124