Polyelemental catalyst structures for fuel cells

A fuel cell comprising:

• a polymer electrolyte membrane (PEM);
• first and second electrode catalyst layers including first and second supports and first and second catalyst materials, respectively, the PEM situated between the first and second electrode catalyst layers, the first and/or second catalyst materials including a plurality of polyelemental catalyst particles, each of the plurality of polyelemental catalyst particles including a region formed of a first metal material, a first core region formed of a second metal material, and a second core region formed of a third metal material, the first core region having interfacial contact with the region, the second core region having interfacial contact with the first core region, the polyelemental catalyst structure including platinum (Pt), a first metal MI, a second metal MII and a third metal MIII, the first metal MI is configured to enhance catalytic activity of Pt, the second metal MII is configured to enhance stability of the polyelemental catalyst structure, and the third metal MIII is configured to enhance covalent bonding between Pt, the first metal MI, the second metal MII and/or the third metal MIII.