Ag Assisted Galvanic Replacement for Selective Pt Deposition on Au Nanostructures

Ag played an auxiliary role in the electrochemical replacement process, alleviating the lattice mismatch between Au and Pt. It promoted the selective reduction of Pt on the edges and vertices, where the surface energy is higher than the flat terraces, forming Au@Pt TOh nanoparticles (Figure S1B). Pt TOh monorim NFs were achieved by etching the inner Au through comproportionation of Au3+ (Figure 2A). As shown in the scheme, eight hexagons and six squares were all open and connected to each other with thin Pt rims.