Influence of sputtering parameters on electrochemical CO2 reduction in sputtered Au electrode

Abstract Electrochemical CO 2 reduction was studied in KCl and KHCO 3 using a Au electrode prepared by sputtering. We investigated the influence of the sputtering parameters (rf power, Ar pressure during deposition, and the distance between substrate and target) and thickness on the reduction potential and products, CO and H 2 . In KCl, the reduction potential, i.e. the overvoltage, was influenced by the Ar pressure, which affects the Au surface geometrical structure/surface area, while in KHCO 3 , the potential remained almost constant, probably due to the neutralizing capacity of KHCO 3 . The other sputtering parameters did not change the CO 2 reduction behavior appreciably.