A Reconstructed Cu₂ P₂ O₇ Catalyst for Selective CO₂ Electroreduction to Multicarbon Products

The electrochemical CO₂ reduction reaction (CO₂ RR) over Cu-based catalysts shows great potential for converting CO₂ into multicarbon (C₂₊ ) fuels and chemicals. Herein, we introduce an A₂ M₂ O₇ structure into a Cu-based catalyst through a solid-state reaction synthesis method. The Cu₂ P₂ O₇ catalyst is electrochemically reduced to metallic Cu with a significant structure evolution from grain aggregates to highly porous structure under CO₂ RR conditions. The reconstructed Cu₂ P₂ O₇ catalyst achieves a Faradaic efficiency of 73.6 % for C₂₊ products at an applied current density of 350 mA cm^-2 , remarkably higher than the CuO counterparts. The reconstructed Cu₂ P₂ O₇ catalyst has a high electrochemically active surface area, abundant defects, and low-coordinated sites. In situ Raman spectroscopy and density functional theory calculations reveal that CO adsorption with bridge and atop configurations is largely improved on Cu with defects and low-coordinated sites, which decreased the energy barrier of the C-C coupling reaction for C₂₊ products.