Diachronic evolvement from tetra-icosahedral to quasi-hexagonal close-packed bimetal clusters

Here we report a diachronic evolvement from tetra-icosahedral Au30Ag12(C 00000000000000000 00000000000000000 00000000000000000 01111111111111110 00000000000000000 01111111111111110 00000000000000000 01111111111111110 00000000000000000 00000000000000000 00000000000000000 CR)24 to quasi-hcp (hexagonal close-packed) Au47Ag19(CCR)32via a one-step reduction, in which the size/structure conversion of the two clusters is not a typical Oswald growth process, but involves interface shrinking followed by core rearrangement and surface polymerization. Au30Ag12(CCR)24 has an aesthetic Au18Ag8 kernel that is composed of four interpenetrating Au10Ag3 icosahedra, while Au47Ag19(CCR)32 has a twisted Au19 core capped by a Au12Ag19 shell that are stacked in a layer-by-layer manner with a quasi-hcp pattern. The discovery of the two clusters not only provides further evidence for icosahedral clusters with longer excited-state lifetime compared to hcp-like clusters, but also discloses a double increase in catalytic reactivity for electrocatalytic oxidation of ethanol over quasi-hcp clusters in comparison with icosahedral clusters. This work provides the rationale for reversing the bottom-up growth process to remake bimetal clusters. Here we report a diachronic evolvement from tetra-icosahedral Au30Ag12(CCR)24 to quasi-hcp (hexagonal close-packed) Au47Ag19(CCR)32 which might be proceeded by the interface shrinking followed by the core rearrangement and surface polymerization.