Assembling Atomically Precise Noble Metal Nanoclusters Using Supramolecular Interactions

Abstract

Supramolecular chemistry (SC) of noble metal nanoclusters (NMNCs) is one of the fascinating areas of contemporary materials science. It is principally concerned with the noncovalent interactions between NMNCs, as well as between NMNCs and molecules or nanoparticles. This review focuses on recent advances in the supramolecular assembly of NMNCs and applications of the resulting structures. We have divided the topics into four distinct subgroups: (i) SC of NMNCs in gaseous and solution phases, (ii) supramolecular interactions of NMNCs in crystal lattices, (iii) supramolecular assemblies of NMNCs with nanoparticles and NMNCs, and (iv) SC of NMNCs with other molecules. The last explores their interactions with fullerenes, cyclodextrins, cucurbiturils, crown ethers, and more. After discussing these topics concisely, various emerging properties of the assembled systems in terms of their mechanical, optical, magnetic, charge-transfer, etc. properties and applications are presented. SC is seen to provide a crucial role to induce new physical and chemical properties in such hybrid nanomaterials. Finally, we highlight the scope for expansion and future research in the area. This review would be useful to those working on functional nanostructures in general and NMNCs in particular.

An atomically precise silver nanocluster for artificial light-harvesting system through supramolecular functionalization

“…[35][36][37][38] Progressing research activities suggest that imposing bulkiness on the surface protecting groups can restrict the intramolecular motion of the NC in solution that can directly decrease the nonradiative relaxation pathway and enhance the emission properties. [39][40][41][42][43][44][45][46][47][48] Therefore, it will be very interesting to encapsulate the ligand-protected Ag NC with a bulky host to build the hostguest adduct at the recognition site of the NC to improve the emission properties by introducing surface rigidity through bulkiness to counteract the thermally activated non-radiative relaxation which will be benecial for the articial LHS fabrication.…”

Single-Electron Charging of Thioctic Acid Monolayer-Protected Gold Clusters

“…Monolayer-protected gold nanoclusters (AuMPCs) have received extensive attention as a hot topic for applications in different fields due to their unique electronic and chemical properties. − They are originated from quantum effects inherent to discrete electron energy states, which arise from gold core dimensions on the nanometer scale. − Sequential single-electron transfer events for both freely diffusing and electrode-attached MPCs can be observed at room temperature similar to either the “Coulomb Staircase” behavior or to sequential electrochemical redox reactions. − MPCs can act as subattoFarad (aF) molecular capacitors resulting from a combination of their small metallic core size and the dielectric properties of the organic protecting layer. Successive one-electron charging steps of the MPC cores, termed quantized double layer charging (QDL), can be observed with potential spacing between these charging events given by Δ V = e / C MPC ( C MPC = capacitance value) that are significantly larger than room temperature thermal energy ( kBT / e ), thus allowing their use as electron donors and acceptors in electron transfer reactions. ,,,− This phenomenon has been observed electrochemically mainly in organic media for hydrophobic alkanethiolate- and arene thiolate-MPCs with a monodisperse core size. ,,− However, these MPCs have limitations for their use in aqueous biological applications due to their low biocompatibility and lack of ω-functional groups that allow interfacing with biomolecules.…”

Modular Cocrystallization of Customized Carboranylthiolate-Protected Copper Nanoclusters via Host–Guest Interactions

“…Atomically precise metal nanoclusters (NCs) constitute a newly emerging class of nanomaterials that bridge molecules and plasmonic nanoparticles and possess molecular-like electronic structures and intriguing physicochemical properties stemming from the quantum confinement effect. − Their highly symmetric geometrical configuration in combination with tunable surface patterns makes these nanoregimes potential building blocks for hierarchical structures. − Unveiling the weak intercluster interactions (H-bonds, π–π interactions, van der Waals interactions, etc.) is of great significance for understanding the crystallization process and the condensed-state properties of metal NCs. − …”