Catalytic Properties of AgCu Bimetallic Nanoparticles for PEMFC Cathode: DFT Study

Noble metals such as Pt have been widely used for catalysts such as in fuel cells. However, due to the high price of Pt, there have been many efforts to reduce the Pt amount or substitute it. We considered AgCu bimetallic nanoparticles as an ORR catalyst. We studied firstly the structural stability of Ag, Cu, and AgCu bimetallic nanoparticles with different sizes and configurations by using DFT calculations. To evaluate the catalytic properties, we determined the oxygen adsorption site and the adsorption energy for each nanoparticle and obtained the energy barrier for oxygen dissociation. Oxygen dissociation is the rate determining step in ORR. As a result, we found the effect of size, configuration, and alloying effect on the oxygen adsorption energy and the energy barrier for oxygen dissociation. Through the comparison of the catalytic properties of each nanoparticle, we propose a new available catalyst for ORR.