Ag-doped Cu nanosheet arrays for efficient hydrogen evolution reaction.

A zinc-infiltration process was adopted to prepare silver-doped copper nanosheet arrays. The larger atomic radius of Ag introduces tensile stress, which lowers the electron density at the s-orbitals of Cu atoms and improves the adsorption capability for hydrogen atoms. As a catalyst for hydrogen evolution, these silver doped copper nanosheet arrays achieved a low overpotential of 103 mV at 10 mA cm ^-2 in 1 M KOH, which is 604 mV lower than that of pure copper foil.