fig1

Figure 1. The optimized geometries and binding energies of (A) a single atomic Pt-N₄ site, (B) a single atomic Bi-N₄ site, and (C) a Pt₄ cluster on N₄ vacancy; (D-G) Four geometries and corresponding adsorption energies of a Pt₄ cluster on a single atomic Bi-N₄ site. The corresponding side views can be found in Supplementary Figure 2.