Promoting CO 2 Electroreduction to Ethane by Iodide-Derived Copper with the Hydrophobic Surface.

Electrochemical reduction of CO 2 to value-added products provides a feasible pathway for mitigating net carbon emissions and storing renewable energy. However, the low dimerization efficiency of the absorbed CO intermediate (*CO) and the competitive hydrogen evolution reaction hinder the selective electroreduction of CO 2 to ethane (C 2 H 6 ) with a high energy density. Here, we designed hydrophobic iodide-derived copper electrodes (I-Cu/Nafion) for reducing CO 2 to C 2 H 6 . The Faradaic efficiency of C 2 H 6 reached 23.37% at -0.7 V vs RHE over the I-Cu/Nafion electrode in an H-type cell, which was about 1.7 times higher than that of the I-Cu electrode. The hydrophobic properties of the I-Cu/Nafion electrodes led to an increase in the local CO 2 concentration and stabilized the Cu + species. In situ Raman characterizations and density functional theory calculations indicate that the enhanced performances could be ascribed to the strong *CO adsorption and decreased the formation energy of *COOH and *COCOH intermediates. This study highlights the effect of the hydrophobic surface on Cu-based catalysts in the electroreduction of CO 2 and provides a promising way to adjust the selectivity of C 2 products.