The article presents a novel nanoporous silver (np-Ag) electrocatalyst that efficiently and selectively reduces carbon dioxide (CO2) to carbon monoxide (CO). Traditional polycrystalline silver electrocatalysts require high overpotentials and have low selectivity. In contrast, the np-Ag catalyst, synthesized through a two-step dealloying process, exhibits a 150 times larger electrochemical surface area and a 20 times higher intrinsic activity compared to polycrystalline silver. This results in a current density over 3,000 times higher and a CO Faradaic efficiency of 92% at moderate overpotentials of <0.50 V. The enhanced performance is attributed to the highly curved internal surface of np-Ag, which stabilizes CO2− intermediates and reduces the thermodynamic barrier. The np-Ag catalyst shows significant advantages over other silver nanostructures and is a promising candidate for large-scale CO2 reduction processes.The article presents a novel nanoporous silver (np-Ag) electrocatalyst that efficiently and selectively reduces carbon dioxide (CO2) to carbon monoxide (CO). Traditional polycrystalline silver electrocatalysts require high overpotentials and have low selectivity. In contrast, the np-Ag catalyst, synthesized through a two-step dealloying process, exhibits a 150 times larger electrochemical surface area and a 20 times higher intrinsic activity compared to polycrystalline silver. This results in a current density over 3,000 times higher and a CO Faradaic efficiency of 92% at moderate overpotentials of <0.50 V. The enhanced performance is attributed to the highly curved internal surface of np-Ag, which stabilizes CO2− intermediates and reduces the thermodynamic barrier. The np-Ag catalyst shows significant advantages over other silver nanostructures and is a promising candidate for large-scale CO2 reduction processes.