Nanocluster growth via “graft-onto”: effects on geometric structures and optical properties

Atomically precise engineering on the nanocluster surface remains highly desirable for the fundamental understanding of how surface structures of a nanocluster contribute to its overall properties. In this paper, the concept of “graft-onto” has been exploited to facilitate nanocluster growth on surface structures. Specifically, the Ag(2)(DPPM)Cl(2) complex is used for re-constructing the surface structure of Pt(1)Ag(28)(SR)(18)(PPh(3))(4) (Pt(1)Ag(28), SR = 1-adamantanethiolate) and producing a size-growth nanocluster – Pt(1)Ag(31)(SR)(16)(DPPM)(3)Cl(3) (Pt(1)Ag(31)). The grafting effect of Ag(2)(DPPM)Cl(2) induces both direct changes on the surface structure (e.g., size growth, structural transformation, and surface rotation) and indirect changes on the kernel structure (from a fcc configuration to an icosahedral configuration). Remarkable differences have been observed by comparing optical properties between Pt(1)Ag(28) and Pt(1)Ag(31). Significantly, Pt(1)Ag(31) exhibits high photo-luminescent intensity with a quantum yield of 29.3%, which is six times that of the Pt(1)Ag(28). Overall, this work presents a new approach (i.e., graft-onto) for the precise dictation of nanocluster surface structures at the atomic level.