Oxygen reduction reaction on Cu-doped Ag cluster for fuel-cell cathode

The development of fuel cells as clean-energy technologies is largely limited by the prohibitive cost of the noble-metal catalysts needed for catalyzing the oxygen reduction reaction (ORR) in fuel cells. A fundamental understanding of catalyst design principle that links material structures to the catalytic activity can accelerate the search for highly active and abundant bimetallic catalysts to replace platinum. Here, we present a first-principles study of ORR on Ag12Cu cluster in alkaline environment. The adsorptions of O-2, OOH, and OH on Cu-doped Ag-13 are stronger than on Ag-13. The d-band centers of adsorption sites show the Cu-doping makes d-electrons transferred to higher energy state, and improves O-2 dissociation. ORR processes on Ag12Cu and Ag-13 indicate Cu-doping can strongly promote ORR, and ORR process can be better preformed on Ag12Cu than on Ag-13. For four-electron transfer, the effective reversible potential is 0.401 V/RHE on Ag12Cu in alkaline medium.