Bimetallic AuAg NPs (NPs) were synthesized via chemical reduction of AuCl3 and AgNO3 and fully characterized by several experimental techniques and theoretical calculations. The plasmon absorptions of these NPs were correlated with the most stable particle structure through different simulations, revealing the most stable structure to be consisted of a gold core and a silver shell. This structural motif was then confirmed by HR-TEM coupled with line-scan EDS and molecular dynamics. Finally, the impact of the nanoparticle composition on their catalytic performance for glycerol electrooxidation was evaluated. The better catalytic performance in terms of the onset potential found for the Au50Ag50 and Au75Ag25 catalysts suggests the existence of a synergistic effect between Au and Ag.