Direct versus ligand-exchange synthesis of [PtAg28(BDT)12(TPP)4]4− nanoclusters: effect of a single-atom dopant on the optoelectronic and chemical properties. Issue 27 (29th June 2017)

• Record Type: Journal Article
• Authors: Bootharaju, Megalamane S.; Kozlov, Sergey M.; Cao, Zhen; Harb, Moussab; Parida, Manas R.; Hedhili, Mohamed N.; Mohammed, Omar F.; Bakr, Osman M.; Cavallo, Luigi; Basset, Jean-Marie
• Is Part Of: Nanoscale. Volume 9:Issue 27(2017)
• Page Start: 9529
• Page End: 9536
• Publication Date: 2017-06-29
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c7nr02844j
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : A single-sized, Pt-doped, dithiolated PtAg28 nanocluster was synthesized through a ligand-exchange strategy. Abstract : Heteroatom doping of atomically precise nanoclusters (NCs) often yields a mixture of doped and undoped products of single-atom difference, whose separation is extremely difficult. To overcome this challenge, novel synthesis methods are required to offer monodisperse doped NCs. For instance, the direct synthesis of PtAg28 NCs produces a mixture of [Ag29 (BDT)12 (TPP)4 ] 3− and [PtAg28 (BDT)12 (TPP)4 ] 4− NCs (TPP: triphenylphosphine; BDT: 1, 3-benzenedithiolate). Here, we designed a ligand-exchange (LE) strategy to synthesize single-sized, Pt-doped, superatomic Ag NCs [PtAg28 (BDT)12 (TPP)4 ] 4− by LE of [Pt2 Ag23 Cl7 (TPP)10 ] NCs with BDTH2 (1, 3-benzenedithiol). The doped NCs were thoroughly characterized by optical and photoelectron spectroscopy, mass spectrometry, total electron count, and time-dependent density functional theory (TDDFT). We show that the Pt dopant occupies the center of the PtAg28 cluster, modulates its electronic structure and enhances its photoluminescence intensity and excited-state lifetime, and also enables solvent interactions with the NC surface. Furthermore, doped NCs showed unique reactivity with metal ions – the central Pt atom of PtAg28 could not be replaced by Au, unlike the central Ag of Ag29 NCs. The achieved synthesis of single-sized PtAg28 clusters will facilitate further applications of the LE strategy for the exploration of novel multimetallic NCs.