Dual Lewis Acid‐Base Sites Regulate Silver‐Copper Bimetallic Oxide Nanowires for Highly Selective Photoreduction of Carbon Dioxide to Methane

Abstract

AbstractHighly selective photoreduction of CO2 to valuable hydrocarbons is of great importance to achieving a carbon‐neutral society. Precisely manipulating the formation of the Metal1⋅⋅⋅C=O⋅⋅⋅Metal2 (M1⋅⋅⋅C=O⋅⋅⋅M2) intermediate on the photocatalyst interface is the most critical step for regulating selectivity, while still a significant challenge. Herein, inspired by the polar electronic structure feature of CO2 molecule, we propose a strategy whereby the Lewis acid‐base dual sites confined in a bimetallic catalyst surface are conducive to forming a M1⋅⋅⋅C=O⋅⋅⋅M2 intermediate precisely, which can promote selectivity to hydrocarbon formation. Employing the Ag2Cu2O3 nanowires with abundant Cu⋅⋅⋅Ag Lewis acid‐base dual sites on the preferred exposed {110} surface as a model catalyst, 100 % selectivity toward photoreduction of CO2 into CH4 has been achieved. Subsequent surface‐quenching experiments and density functional theory (DFT) calculations verify that the Cu⋅⋅⋅Ag Lewis acid‐base dual sites do play a vital role in regulating the M1⋅⋅⋅C=O⋅⋅⋅M2 intermediate formation that is considered to be prone to convert CO2 into hydrocarbons. This study reports a highly selective CO2 photocatalyst, which was designed on the basis of a newly proposed theory for precise regulation of reaction intermediates. Our findings will stimulate further research on dual‐site catalyst design for CO2 reduction to hydrocarbons.