AuAg alloy nanoparticles (NPs) have stimulated increasing interest because of their unique optical, electronic, and catalytic properties. One feature of these NPs is the tunability of surface plasmon resonance (SPR) frequency by the composition of the alloy, from 520 nm (for Au) to 400 nm (for Ag). It has been also reported that AuAg alloy NPs show enhanced catalytic activity for CO oxidation c…