Ag nanoparticle embedded Cu nanoporous hybrid arrays for the selective electrocatalytic reduction of CO2 towards ethylene

Abstract

Electrocatalytic reduction of carbon dioxide (CO₂RR) driven by renewable electricity is a promising strategy for chemical recycling of carbon. It can alleviate the carbon emission by reducing the carbon dioxide concentrations in the atmosphere, transforming low energy density renewable energy into high energy density carbonaceous fuels. Copper-based catalysts play an important role in the field of electrocatalytic CO₂ because of their ability to reduce CO₂ to hydrocarbons. However, problems such as high overpotential, catalyst deactivation, and uncontrollable product selectivity limit their further development. Herein, we construct Ag/Cu and Zn/Cu composite structures for CO₂ reduction by employing tiny Ag nanoparticles and Zn nanocones uniformly distributed on the surface of porous network Cu nanowires. It is found that Ag/Cu composite structures are more active for the reduction of CO₂ to C₂H₄, compared to those of Zn modified. The faradaic efficiency of CO₂ reduction to ethylene reaches 41.3% and it remains stable for more than 8 hours. Theoretical calculations show that the modification of silver regulates the electronic structure of highly porous copper at the Cu/Ag interface, accelerates the process of carbon dioxide reduction of the first electron, enhances the adsorption of *CO and further facilitates *CO dimerization to ethylene. Therefore, the strategy of silver-modified porous copper pre-catalyst is a promising approach for CO₂ reduction to hydrocarbons.