The mechanism of high electrocatalytic activity and stability of the Pt3Co alloy embedded into the lattice by Au or Rh atoms

In proton exchange membrane fuel cells (PEMFCs), the most advanced catalysts are mainly carbon loaded with platinum (Pt), but the cathodic catalytic active center is too low to match the oxidation activity and rate at the anode. Co atoms doped into the lattice of Pt alloy change the electronic structure of platinum and reduce the binding energy of oxygen atoms. Au or Rh atoms embedded into the lattice of Pt 3 Co alloy compensate the defect and enhance the activity and rate of the oxygen reduction. Through base on density functional theory (DFT), the adsorption energy for oxygen on Pt 3 Co, Au-Pt 3 Co, and Rh-Pt 3 Co and the segregation energy of Co atoms were calculated. The results show that Au or Rh doped weakens the binding energy of Pt for oxygen on the Pt 3 Co alloy and improves the activity and stability of oxygen reduction. Compared with Rh, the introduction of Au element shows better effects in the electrocatalytic reaction process. Graphical Abstract