Isotopic Exchange of Atomically Precise Nanoclusters with Materials of Varying Dimensions: From Nanoscale to Bulk

Abstract

We present isotopic exchange reactions of atomically precise silver nanoclusters (NCs) with materials of different dimensions, namely, NCs, plasmonic nanoparticles (NPs), and bulk metals, all made of silver. Isotopically pure 109Ag25(DMBT)18 – and 107Ag25(DMBT)18 – (DMBT is 2,4-dimethyl benzene thiol) were reacted with Ag NPs of different sizes in the range of ∼2–11 nm, protected with the same ligand. The exchange of 107Ag/109Ag atoms in the NC was monitored using electrospray ionization mass spectrometry. The reaction kinetics was analyzed by fitting the temporal evolution of the reactant concentration to a kinetic model. The reaction timescales of NC–NP reactions were significantly longer compared to those of the NC–NC exchange process under similar conditions. Differences between NC–NC exchange and NC–NP exchange highlighted the importance of the structure in controlling the reaction. Moreover, isotopic exchanges of the NC were also studied with the bulk metal to obtain a complete understanding of how the kinetics of atom transfer varies upon changing the size of the reacting partner from nanoscale to bulk.

A concise guide to chemical reactions of atomically precise noble metal nanoclusters

“…Recently, Chakraborty et al reported the dynamics of isotopic exchange reactions of isoto-pically pure Ag nanocluster with different dimensions of metallic Ag, like nanoclusters, plasmonic NPs, and bulk. 289 Isotopically pure 107 Ag 25 (DMBT) 18 and 108 Ag 25 (DMBT) 18 was reacted with different sizes of Ag@DMBT NPs (naturally abundant Ag). With the increase in the NP size, the rate of atomic exchange was reduced.…”

Interparticle Antigalvanic Reactions of Atomically Precise Silver Nanoclusters with Plasmonic Gold Nanoparticles: Interfacial Control of Atomic Exchange

“…NP−NC reactions are spontaneous and stoichiometric in nature. 52,71 Figure 3B shows the time-dependent evolution of the mass spectral features of [Ag 25 (DMBT) 18 ] − NC upon interaction with Au NP (full range MS in Figure S7). As the reaction progressed, the peak corresponding to the parent species, [Ag 25 (DMBT) 18 ] − NC (m/z 5166), gradually shifted toward a higher mass species, [Ag 24 Au(DMBT) 18 ] − NC (m/z 5255), NC (m/z 5344) was also observed at a reasonable intensity (isotopic distribution patterns in Figure S8).…”

“…72 A later study on the kinetics of isotopic exchanges showed a size dependence when the reacting partner was varied from the nanoscale to bulk metal with an isotopically pure [Ag 25 (SR) 18 ] − NC. 52 A recent study showed [Ag 25 (SR) 18 ] − NC-meditated site-selective etching of anisotropic Au nanotriangles (Au NTs). 73 ] − and CuO NP reaction, which induced the aggregation of Cu-doped NC leading to spherical superstructures.…”

“…Atomic exchange during nanocluster–nanoparticle (or interparticle) reactions is a relatively less explored area of study. Ligand-exchange, − metal-exchange, − and isotopic-exchange − reactions of atomically precise metal NCs are well-known. ,,,, Like molecules, atomically precise metal NCs undergo internanocluster (or intercluster) reactions in solution. − Bimetallic and trimetallic NCs have also been prepared using intercluster reactions. , Studies on the intercluster reaction mechanism suggest a pathway for the exchange of metal or metal–ligand fragments . The thiolate monolayer protecting the NC surface is dynamic in nature, , and the metal–ligand interface controls the atom transfer in an intercluster reaction .…”

The one/two atom size-reduction of [Au23SCy16]−induced by the [Au6(dppp)4]2+cluster

“…For example, the size- and framework-maintained metal exchange occurs in the reaction of [Ag 25 (DMBT) 18 ] − with [Au 25 (PET) 18 ] − , 14 [Ag 7 (H){S 2 P(O i Pr) 2 } 6 ] with [Cu 7 (H){S 2 P(O i Pr) 2 } 6 ], 15 and the isotopic exchange reactions of [ 107/109 Ag 25 (DMBT) 18 ] − (ref. 16 ) and [ 107/109 Ag 29 (BDT) 12 (TPP) 4 3− ]. 17 Of note, the inter-cluster reactions between two structurally distinct clusters have also been reported.…”