Highly-Exposed Single-Interlayered Cu Edges Enable High-Rate CO2-to-CH4 Electrosynthesis

The electrochemical CO2 reduction to CH4 is a promising approach for producing highly specific combustion fuel but has relatively poor selectivity and activity at high-current-density electrolysis. In this work, ultrathin CuGaO2 nanosheets with highly exposed single-interlayered Cu edges are synthesized via an induced anisotropic growth strategy. Density functional theory calculations indicate that the exposed single-interlayered Cu(I) edges on the (001) surface of CuGaO2 present a high-density of single-atomic Cu sites, which feature excellent CO2 electroreduction catalytic activity toward CH4. The CuGaO2 nanosheet catalysts exhibit efficient and stable CO2-to-CH4 electroreduction with Faradaic efficiency (FECH4) of 71.7% at a high current density of -1 A cm(-2), corresponding to a superior CH4 partial current density of 717 +/- 33 mA cm(-2). This work suggests an attractive design strategy for tuning both the crystal facets and Cu-Cu distance to promote the CH4 electrosynthesis at high-current-density CO2 reduction.

Automated summary

In this study, ultrathin CuGaO2 nanosheets with highly exposed single-interlayered Cu edges were synthesized, and they exhibited excellent CO2 electroreduction catalytic activity towards CH4. The results suggest a design strategy for promoting CH4 electrosynthesis by tuning both the crystal facets and Cu-Cu distance.