Gas diffusion enhanced electrode with ultrathin superhydrophobic macropore structure for acidic CO<sub>2</sub> electroreduction.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38225248.
- Also identified by DOI 10.1038/s41467-024-44722-4 and PMC identifier 10789815.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Carbon dioxide (CO<sub>2</sub>) electroreduction reaction (CO<sub>2</sub>RR) offers a promising strategy for the conversion of CO<sub>2</sub> into valuable chemicals and fuels. CO<sub>2</sub>RR in acidic electrolytes would have various advantages due to the suppression of carbonate formation. However, its reaction rate is severely limited by the slow CO<sub>2</sub> diffusion due to the absence of hydroxide that facilitates the CO<sub>2</sub> diffusion in an acidic environment. Here, we design an optimal architecture of a gas diffusion electrode (GDE) employing a copper-based ultrathin superhydrophobic macroporous layer, in which the CO<sub>2</sub> diffusion is highly enhanced. This GDE retains its applicability even under mechanical deformation conditions. The CO<sub>2</sub>RR in acidic electrolytes exhibits a Faradaic efficiency of 87% with a partial current density [Formula: see text] of -1.6 A cm<sup>-2</sup> for multicarbon products (C<sub>2+</sub>), and [Formula: see text] of -0.34 A cm<sup>-2</sup> when applying dilute 25% CO<sub>2</sub>. In a highly acidic environment, C<sub>2+</sub> formation occurs via a second order reaction which is controlled by both the catalyst and its hydroxide.