[Pt1Ag37(SAdm)21(Dppp)3Cl6]2+: intercluster transformation and photochemical properties

Abstract

Ligand-exchange-induced structure transformation has been exploited as an effective approach to dictate the size and structure of nanoparticles with atomic precision. However, phosphine ligand induced intercluster transformation remains rarely explored. Herein, we report the controllable preparation and the structural elucidation of a [Pt₁Ag₃₇(SAdm)₂₁(Dppp)₃Cl₆]²⁺ nanocluster (Pt₁Ag₃₇; where Dppp is 1,3-bis(diphenyphosphino)propane and HSAdm is 1-adamantanethiol). Notably, the reaction of Pt₁Ag₃₇ with PPh₃ triggers an intercluster transformation, giving rise to a stable and smaller-sized nanocluster, [Pt₁Ag₂₈(SAdm)₁₈(PPh₃)₄]²⁺ (Pt₁Ag₂₈). Such an intercluster transformation is systematically monitored with ESI-MS and UV-vis. The photochemical properties of Pt₁Ag₃₇ and Pt₁Ag₂₈ nanoclusters are further investigated. Of note, in the presence of chiral Bdpp diphosphines (Bdpp = 2,4-bis-(diphenylphosphino) pentane), the enantiomeric Pt₁Ag₃₇(SAdm)₂₁(R/S-Bdpp)₃Cl₆ (R/S-Pt₁Ag₃₇) are obtained, and such chiral nanoclusters displayed obvious optical activity. The results in this work hopefully shed light on the future preparation of metal nanoclusters for customized applications.