Cascade Reactions in Nanozymes: Spatially Separated Active Sites inside Ag-Core–Porous-Cu-Shell Nanoparticles for Multistep Carbon Dioxide Reduction to Higher Organic Molecules

Enzymes can perform complex multistep cascade reactions by linking multiple distinct catalytic sites via substrate channeling. We mimic this feature in a generalized approach with an electrocatalytic nanoparticle for the carbon dioxide reduction reaction comprising a Ag core surrounded by a porous Cu shell, providing different active sites in nanoconfined volumes. The architecture of the nanozyme provides the basis for a cascade reaction, which promotes C–C coupling reactions. The first step occurs on the Ag core, and the subsequent steps on the porous copper shell, where a sufficiently high CO concentration due to the nanoconfinement facilitates C–C bond formation. The architecture yields the formation of n-propanol and propionaldehyde at potentials as low as −0.6 V vs RHE.