Supramolecular Gold Chemistry: From Atomically Precise Thiolate-Protected Gold Nanoclusters to Gold-Thiolate Nanostructures

A special issue of Nanomaterials (ISSN 2079-4991).

Deadline for manuscript submissions: closed (31 December 2019) | Viewed by 68589

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Institut Lumière Matière UMR 5306, Université Claude Bernard Lyon 1, CNRS, Univ Lyon, F-69100 Villeurbanne, France
Interests: structural and optical properties of isolated biomolecules; structural and optical properties of isolated nanohybrids; bioparticles; liganded nanoclusters; nonlinear optics; mass spectrometry
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Special Issue Information

Dear Colleagues,

The chemistry of the sulfur–gold bond is extremely rich and leads to hybrid materials. Such materials encompass gold thiolate coordination oligomers, for instance [Au(I)(SR)]n, where SR stands for a chemical group containing a sulfur atom and atomically well-defined clusters [AunSRm], or supramolecular assemblies like Au(I)(SR). While the majority of gold atoms in the nanoparticles are in the Au(0) state under strong reducing conditions, gold atoms in supramolecular assemblies like Au(I)(SR) NPs are in the gold(I) state. In atomically well-defined clusters of [AunSRm] stoichiometry, a subtle balance between the Au(0) core and the Au(I)–SR shell leads to fascinating material properties and in particular to highly tunable optical properties.
The Special Issue on “Supramolecular Gold Chemistry” is intended to provide a unique international forum aimed at covering a broad description of results involving the chemistry of the sulfur–gold interface leading to hybrid materials, ranging from gold thiolate coordination polymers, to thiolate protected gold nanoclusters and gold–thiolate supramolecular assemblies. Scientists working both experimentally and theoretically in a wide range of disciplines are invited to contribute to this issue.

Prof. Rodolphe Antoine
Guest Editor

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Keywords

  • Gold, silver
  • Thiolate
  • Supramolecular chemistry
  • Nanoparticles
  • Nanoclusters
  • Gold–thiolate polymers
  • Structural characterization
  • Optical properties

Published Papers (13 papers)

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Editorial

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3 pages, 195 KiB  
Editorial
Supramolecular Gold Chemistry: From Atomically Precise Thiolate-Protected Gold Nanoclusters to Gold-Thiolate Nanostructures
by Rodolphe Antoine
Nanomaterials 2020, 10(2), 377; https://doi.org/10.3390/nano10020377 - 21 Feb 2020
Cited by 16 | Viewed by 2838
Abstract
Supramolecular chemistry is defined as chemistry beyond the molecule [...] Full article

Research

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9 pages, 2536 KiB  
Article
6-Aza-2-Thio-Thymine Stabilized Gold Nanoclusters as Photoluminescent Probe for Protein Detection
by Hao-Hua Deng, Xiao-Qiong Shi, Paramasivam Balasubramanian, Kai-Yuan Huang, Ying-Ying Xu, Zhong-Nan Huang, Hua-Ping Peng and Wei Chen
Nanomaterials 2020, 10(2), 281; https://doi.org/10.3390/nano10020281 - 7 Feb 2020
Cited by 11 | Viewed by 3436
Abstract
This study puts forward an efficient method for protein detection in virtue of the tremendous fluorescence enhancement property of 6-aza-2-thio-thymine protected gold nanoclusters (ATT-AuNCs). In-depth studies of the protein-induced photoluminescence enhancement mechanism illustrate the mechanism of the interaction between ATT-AuNCs and protein. This [...] Read more.
This study puts forward an efficient method for protein detection in virtue of the tremendous fluorescence enhancement property of 6-aza-2-thio-thymine protected gold nanoclusters (ATT-AuNCs). In-depth studies of the protein-induced photoluminescence enhancement mechanism illustrate the mechanism of the interaction between ATT-AuNCs and protein. This new-established probe enables feasible and sensitive quantification of the concentrations of total protein in real samples, such as human serum, human plasma, milk, and cell extracts. The results of this proposed method are in good agreement with those determined by the classical bicinchoninic acid method (BCA method). Full article
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12 pages, 2305 KiB  
Article
A New Lamellar Gold Thiolate Coordination Polymer, [Au(m-SPhCO2H)]n, for the Formation of Luminescent Polymer Composites
by Oleksandra Veselska, Nathalie Guillou, Gilles Ledoux, Chia-Ching Huang, Katerina Dohnalova Newell, Erik Elkaïm, Alexandra Fateeva and Aude Demessence
Nanomaterials 2019, 9(10), 1408; https://doi.org/10.3390/nano9101408 - 2 Oct 2019
Cited by 9 | Viewed by 3536
Abstract
The photoluminescence of gold thiolate clusters brings about many potential applications, but its origin is still elusive because of its complexity. A strategy in understanding the structure–properties relationship is to study closely related neutral gold thiolate coordination polymers (CPs). Here, a new CP [...] Read more.
The photoluminescence of gold thiolate clusters brings about many potential applications, but its origin is still elusive because of its complexity. A strategy in understanding the structure–properties relationship is to study closely related neutral gold thiolate coordination polymers (CPs). Here, a new CP is reported, [Au(m-SPhCO2H)]n. Its structure is lamellar with an inorganic layer made of Au–S–Au–S helical chains, similar to the [Au(p-SPhCO2H)]n analog. An in-depth study of its photophysical properties revealed that it is a bright yellow phosphorescent emitter with a band centered at 615 nm and a quantum yield (QY) of 19% at room temperature and in a solid state. More importantly, a comparison to the para-analog, which has a weak emission, displayed a strong effect of the position of the electron withdrawing group (EWG) on the luminescent properties. In addition, [Au(m-SPhCO2H)]n CPs were mixed with organic polymers to generate transparent and flexible luminescent thin films. The ability to tune the emission position with the appropriate contents makes these nontoxic polymer composites promising materials for lighting devices. Full article
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14 pages, 2775 KiB  
Article
New Evidence of the Bidentate Binding Mode in 3-MBA Protected Gold Clusters: Analysis of Aqueous 13–18 kDa Gold-Thiolate Clusters by HPLC-ESI-MS Reveals Special Compositions Aun(3-MBA)p, (n = 48–67, p = 26–30)
by David M. Black, M. Mozammel Hoque, Germán Plascencia-Villa and Robert L. Whetten
Nanomaterials 2019, 9(9), 1303; https://doi.org/10.3390/nano9091303 - 11 Sep 2019
Cited by 6 | Viewed by 3289
Abstract
Gold clusters protected by 3-MBA ligands (MBA = mercaptobenzoic acid, –SPhCO2H) have attracted recent interest due to their unusual structures and their advantageous ligand-exchange and bioconjugation properties. Azubel et al. first determined the core structure of an Au68-complex, which [...] Read more.
Gold clusters protected by 3-MBA ligands (MBA = mercaptobenzoic acid, –SPhCO2H) have attracted recent interest due to their unusual structures and their advantageous ligand-exchange and bioconjugation properties. Azubel et al. first determined the core structure of an Au68-complex, which was estimated to have 32 ligands (3-MBA groups). To explain the exceptional structure-composition and reaction properties of this complex, and its larger homologs, Tero et al. proposed a “dynamic stabilization” via carboxyl O–H––Au interactions. Herein, we report the first results of an integrated liquid chromatography/mass spectrometer (LC/MS) analysis of unfractionated samples of gold/3-MBA clusters, spanning a narrow size range 13.4 to 18.1 kDa. Using high-throughput procedures adapted from bio-macromolecule analyses, we show that integrated capillary high performance liquid chromatography electrospray ionization mass spectrometer (HPLC-ESI-MS), based on aqueous-methanol mobile phases and ion-pairing reverse-phase chromatography, can separate several major components from the nanoclusters mixture that may be difficult to resolve by standard native gel electrophoresis due to their similar size and charge. For each component, one obtains a well-resolved mass spectrum, nearly free of adducts or signs of fragmentation. A consistent set of molecular mass determinations is calculated from detected charge-states tunable from 3− (or lower), to 2+ (or higher). One thus arrives at a series of new compositions (n, p) specific to the Au/3-MBA system. The smallest major component is assigned to the previously unknown (48, 26); the largest one is evidently (67, 30), vs. the anticipated (68, 32). Various explanations for this discrepancy are considered. A prospective is given for the various members of this novel series, along with a summary of the advantages and present limitations of the micro-scale integrated LC/MS approach in characterizing such metallic-core macro-molecules, and their derivatives. Full article
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14 pages, 3465 KiB  
Article
In Situ Decoration of Gold Nanoparticles on Graphene Oxide via Nanosecond Laser Ablation for Remarkable Chemical Sensing and Catalysis
by Parvathy Nancy, Anju K Nair, Rodolphe Antoine, Sabu Thomas and Nandakumar Kalarikkal
Nanomaterials 2019, 9(9), 1201; https://doi.org/10.3390/nano9091201 - 26 Aug 2019
Cited by 31 | Viewed by 5721
Abstract
Gold decorated graphene-based nano-hybrids find extensive research interest due to their enhanced chemical catalytic performance and biochemical sensing. The unique physicochemical properties and the very large surface area makes them propitious platform for the rapid buildouts of science and technology. Graphene serves as [...] Read more.
Gold decorated graphene-based nano-hybrids find extensive research interest due to their enhanced chemical catalytic performance and biochemical sensing. The unique physicochemical properties and the very large surface area makes them propitious platform for the rapid buildouts of science and technology. Graphene serves as an outstanding matrix for anchoring numerous nanomaterials because of its atomically thin 2D morphological features. Herein, we have designed a metal-graphene nano-hybrid through pulsed laser ablation. Commercially available graphite powder was employed for the preparation of graphene oxide (GO) using modified Hummers’ method. A solid, thin gold (Au) foil was ablated in an aqueous suspension of GO using second harmonic wavelength (532 nm) of the Nd:YAG laser for immediate generation of the Au-GO nano-hybrid. The synthesis strategy employed here does not entail any detrimental chemical reagents and hence avoids the inclusion of reagent byproducts to the reaction mixture, toxicity, and environmental or chemical contamination. Optical and morphological characterizations were performed to substantiate the successful anchoring of Au nanoparticles (Au NPs) on the GO sheets. Remarkably, these photon-generated nano-hybrids can act as an excellent surface enhanced Raman spectroscopy (SERS) platform for the sensing/detection of the 4-mercaptobenzoic acid (4-MBA) with a very low detection limit of 1 × 10−12 M and preserves better reproducibility also. In addition, these hybrid materials were found to act as an effective catalyst for the reduction of 4-nitrophenol (4-NP). Thus, this is a rapid, mild, efficient and green synthesis approach for the fabrication of active organometallic sensors and catalysts. Full article
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12 pages, 3912 KiB  
Article
New Perspectives on the Electronic and Geometric Structure of Au70S20(PPh3)12 Cluster: Superatomic-Network Core Protected by Novel Au123-S)10 Staple Motifs
by Zhimei Tian, Yangyang Xu and Longjiu Cheng
Nanomaterials 2019, 9(8), 1132; https://doi.org/10.3390/nano9081132 - 6 Aug 2019
Cited by 12 | Viewed by 3391
Abstract
In order to increase the understanding of the recently synthesized Au70S20(PPh3)12 cluster, we used the divide and protect concept and superatom network model (SAN) to study the electronic and geometric of the cluster. According to the [...] Read more.
In order to increase the understanding of the recently synthesized Au70S20(PPh3)12 cluster, we used the divide and protect concept and superatom network model (SAN) to study the electronic and geometric of the cluster. According to the experimental coordinates of the cluster, the study of Au70S20(PPh3)12 cluster was carried out using density functional theory calculations. Based on the superatom complex (SAC) model, the number of the valence electrons of the cluster is 30. It is not the number of valence electrons satisfied for a magic cluster. According to the concept of divide and protect, Au70S20(PPh3)12 cluster can be viewed as Au-core protected by various staple motifs. On the basis of SAN model, the Au-core is composed of a union of 2e-superatoms, and 2e-superatoms can be Au3, Au4, Au5, or Au6. Au70S20(PPh3)12 cluster should contain fifteen 2e-superatoms on the basis of SAN model. On analyzing the chemical bonding features of Au70S20(PPh3)12, we showed that the electronic structure of it has a network of fifteen 2e-superatoms, abbreviated as 15 × 2e SAN. On the basis of the divide and protect concept, Au70S20(PPh3)12 cluster can be viewed as Au4616+[Au123-S)108−]2[PPh3]12. The Au4616+ core is composed of one Au2212+ innermost core and ten surrounding 2e-Au4 superatoms. The Au2212+ innermost core can either be viewed as a network of five 2e-Au6 superatoms, or be considered as a 10e-superatomic molecule. This new segmentation method can properly explain the structure and stability of Au70S20(PPh3)12 cluster. A novel extended staple motif [Au123-S)10]8− was discovered, which is a half-cage with ten µ3-S units and six teeth. The six teeth staple motif enriches the family of staple motifs in ligand-protected Au clusters. Au70S20(PPh3)12 cluster derives its stability from SAN model and aurophilic interactions. Inspired by the half-cage motif, we design three core-in-cage clusters with cage staple motifs, Cu6@Au123-S)8, Ag6@Au123-S)8 and Au6@Au123-S)8, which exhibit high thermostability and may be synthesized in future. Full article
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13 pages, 4255 KiB  
Article
Gold Nanoclusters: Bridging Gold Complexes and Plasmonic Nanoparticles in Photophysical Properties
by Meng Zhou, Chenjie Zeng, Qi Li, Tatsuya Higaki and Rongchao Jin
Nanomaterials 2019, 9(7), 933; https://doi.org/10.3390/nano9070933 - 28 Jun 2019
Cited by 34 | Viewed by 8899
Abstract
Recent advances in the determination of crystal structures and studies of optical properties of gold nanoclusters in the size range from tens to hundreds of gold atoms have started to reveal the grand evolution from gold complexes to nanoclusters and further to plasmonic [...] Read more.
Recent advances in the determination of crystal structures and studies of optical properties of gold nanoclusters in the size range from tens to hundreds of gold atoms have started to reveal the grand evolution from gold complexes to nanoclusters and further to plasmonic nanoparticles. However, a detailed comparison of their photophysical properties is still lacking. Here, we compared the excited state behaviors of gold complexes, nanolcusters, and plasmonic nanoparticles, as well as small organic molecules by choosing four typical examples including the Au10 complex, Au25 nanocluster (1 nm metal core), 13 diameter Au nanoparticles, and Rhodamine B. To compare their photophysical behaviors, we performed steady-state absorption, photoluminescence, and femtosecond transient absorption spectroscopic measurements. It was found that gold nanoclusters behave somewhat like small molecules, showing both rapid internal conversion (<1 ps) and long-lived excited state lifetime (about 100 ns). Unlike the nanocluster form in which metal–metal transitions dominate, gold complexes showed significant charge transfer between metal atoms and surface ligands. Plasmonic gold nanoparticles, on the other hand, had electrons being heated and cooled (~100 ps time scale) after photo-excitation, and the relaxation was dominated by electron–electron scattering, electron–phonon coupling, and energy dissipation. In both nanoclusters and plasmonic nanoparticles, one can observe coherent oscillations of the metal core, but with different fundamental origins. Overall, this work provides some benchmarking features for organic dye molecules, organometallic complexes, metal nanoclusters, and plasmonic nanoparticles. Full article
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7 pages, 1023 KiB  
Article
Catenane Structures of Homoleptic Thioglycolic Acid-Protected Gold Nanoclusters Evidenced by Ion Mobility-Mass Spectrometry and DFT Calculations
by Clothilde Comby-Zerbino, Martina Perić, Franck Bertorelle, Fabien Chirot, Philippe Dugourd, Vlasta Bonačić-Koutecký and Rodolphe Antoine
Nanomaterials 2019, 9(3), 457; https://doi.org/10.3390/nano9030457 - 19 Mar 2019
Cited by 15 | Viewed by 4726
Abstract
Thiolate-protected metal nanoclusters have highly size- and structure-dependent physicochemical properties and are a promising class of nanomaterials. As a consequence, for the rationalization of their synthesis and for the design of new clusters with tailored properties, a precise characterization of their composition and [...] Read more.
Thiolate-protected metal nanoclusters have highly size- and structure-dependent physicochemical properties and are a promising class of nanomaterials. As a consequence, for the rationalization of their synthesis and for the design of new clusters with tailored properties, a precise characterization of their composition and structure at the atomic level is required. We report a combined ion mobility-mass spectrometry approach with density functional theory (DFT) calculations for determination of the structural and optical properties of ultra-small gold nanoclusters protected by thioglycolic acid (TGA) as ligand molecules, Au10(TGA)10. Collision cross-section (CCS) measurements are reported for two charge states. DFT optimized geometrical structures are used to compute CCSs. The comparison of the experimentally- and theoretically-determined CCSs allows concluding that such nanoclusters have catenane structures. Full article
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7 pages, 1640 KiB  
Communication
Intramolecular Metal Exchange Reaction Promoted by Thiol Ligands
by Yangfeng Li, Man Chen, Shuxin Wang and Manzhou Zhu
Nanomaterials 2018, 8(12), 1070; https://doi.org/10.3390/nano8121070 - 19 Dec 2018
Cited by 15 | Viewed by 4407
Abstract
The synthesis of an alloy nanocluster that is atomically precise is the key to understanding the metal synergy effect at the atomic level. Using the Ag2Au25(SR)18 nanocluster as a model, we reported a third approach for the metal [...] Read more.
The synthesis of an alloy nanocluster that is atomically precise is the key to understanding the metal synergy effect at the atomic level. Using the Ag2Au25(SR)18 nanocluster as a model, we reported a third approach for the metal exchange reaction, that is, intramolecular metal exchange. The surface adsorbed metal ions (i.e., Ag) can be exchanged with the kernel metal atoms (i.e., Au) that are promoted by thiol ligands. The exchanged gold atoms can be further stripped by the thiol ligands, and produce the AgxAu25−x(SR)18 nanocluster. Full article
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Review

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24 pages, 8236 KiB  
Review
Origin of the Photoluminescence of Metal Nanoclusters: From Metal-Centered Emission to Ligand-Centered Emission
by Tai-Qun Yang, Bo Peng, Bing-Qian Shan, Yu-Xin Zong, Jin-Gang Jiang, Peng Wu and Kun Zhang
Nanomaterials 2020, 10(2), 261; https://doi.org/10.3390/nano10020261 - 4 Feb 2020
Cited by 144 | Viewed by 10247
Abstract
Recently, metal nanoclusters (MNCs) emerged as a new class of luminescent materials and have attracted tremendous interest in the area of luminescence-related applications due to their excellent luminous properties (good photostability, large Stokes shift) and inherent good biocompatibility. However, the origin of photoluminescence [...] Read more.
Recently, metal nanoclusters (MNCs) emerged as a new class of luminescent materials and have attracted tremendous interest in the area of luminescence-related applications due to their excellent luminous properties (good photostability, large Stokes shift) and inherent good biocompatibility. However, the origin of photoluminescence (PL) of MNCs is still not fully understood, which has limited their practical application. In this mini-review, focusing on the origin of the photoemission emission of MNCs, we simply review the evolution of luminescent mechanism models of MNCs, from the pure metal-centered quantum confinement mechanics to ligand-centered p band intermediate state (PBIS) model via a transitional ligand-to-metal charge transfer (LMCT or LMMCT) mechanism as a compromise model. Full article
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21 pages, 4547 KiB  
Review
Gold Nanoclusters as Electrocatalysts for Energy Conversion
by Tokuhisa Kawawaki and Yuichi Negishi
Nanomaterials 2020, 10(2), 238; https://doi.org/10.3390/nano10020238 - 29 Jan 2020
Cited by 36 | Viewed by 6875
Abstract
Gold nanoclusters (Aun NCs) exhibit a size-specific electronic structure unlike bulk gold and can therefore be used as catalysts in various reactions. Ligand-protected Aun NCs can be synthesized with atomic precision, and the geometric structures of many Aun NCs have [...] Read more.
Gold nanoclusters (Aun NCs) exhibit a size-specific electronic structure unlike bulk gold and can therefore be used as catalysts in various reactions. Ligand-protected Aun NCs can be synthesized with atomic precision, and the geometric structures of many Aun NCs have been determined by single-crystal X-ray diffraction analysis. In addition, Aun NCs can be doped with various types of elements. Clarification of the effects of changes to the chemical composition, geometric structure, and associated electronic state on catalytic activity would enable a deep understanding of the active sites and mechanisms in catalytic reactions as well as key factors for high activation. Furthermore, it may be possible to synthesize Aun NCs with properties that surpass those of conventional catalysts using the obtained design guidelines. With these expectations, catalyst research using Aun NCs as a model catalyst has been actively conducted in recent years. This review focuses on the application of Aun NCs as an electrocatalyst and outlines recent research progress. Full article
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18 pages, 2614 KiB  
Review
Reduction of Tetrachloroaurate(III) Ions With Bioligands: Role of the Thiol and Amine Functional Groups on the Structure and Optical Features of Gold Nanohybrid Systems
by Ditta Ungor, Imre Dékány and Edit Csapó
Nanomaterials 2019, 9(9), 1229; https://doi.org/10.3390/nano9091229 - 29 Aug 2019
Cited by 44 | Viewed by 4404
Abstract
In this review, the presentation of the synthetic routes of plasmonic gold nanoparticles (Au NPs), fluorescent gold nanoclusters (Au NCs), as well as self-assembled Au-containing thiolated coordination polymers (Au CPs) was highlighted. We exclusively emphasize the gold products that are synthesized by the [...] Read more.
In this review, the presentation of the synthetic routes of plasmonic gold nanoparticles (Au NPs), fluorescent gold nanoclusters (Au NCs), as well as self-assembled Au-containing thiolated coordination polymers (Au CPs) was highlighted. We exclusively emphasize the gold products that are synthesized by the spontaneous interaction of tetrachloroaurate(III) ions (AuCl4¯) with bioligands using amine and thiolate derivatives, including mainly amino acids. The dominant role of the nature of the applied reducing molecules as well as the experimental conditions (concentration of the precursor metal ion, molar ratio of the AuCl4¯ ions and biomolecules; pH, temperature, etc.) of the syntheses on the size and structure-dependent optical properties of these gold nanohybrid materials have been summarized. While using the same reducing and stabilizing biomolecules, the main differences on the preparation conditions of Au NPs, Au NCs, and Au CPs have been interpreted and the reducing capabilities of various amino acids and thiolates have been compared. Moreover, various fabrication routes of thiol-stabilized plasmonic Au NPs, as well as fluorescent Au NCs and self-assembled Au CPs have been presented via the formation of (Au(I)-SR)n periodic structures as intermediates. Full article
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17 pages, 9082 KiB  
Review
Heterogeneous Cross-Coupling over Gold Nanoclusters
by Quanquan Shi, Zhaoxian Qin, Hui Xu and Gao Li
Nanomaterials 2019, 9(6), 838; https://doi.org/10.3390/nano9060838 - 1 Jun 2019
Cited by 31 | Viewed by 4658
Abstract
Au clusters with the precise numbers of gold atoms, a novel nanogold material, have recently attracted increasing interest in the nanoscience because of very unique and unexpected properties. The unique interaction and electron transfer between gold clusters and reactants make the clusters promising [...] Read more.
Au clusters with the precise numbers of gold atoms, a novel nanogold material, have recently attracted increasing interest in the nanoscience because of very unique and unexpected properties. The unique interaction and electron transfer between gold clusters and reactants make the clusters promising catalysts during organic transformations. The AunLm nanoclusters (where L represents organic ligands and n and m mean the number of gold atoms and ligands, respectively) have been well investigated and developed for selective oxidation, hydrogenation, photo-catalysis, and so on. These gold clusters possess unique frameworks, providing insights into the catalytic processes and an excellent arena to correlate the atomic frameworks with their intrinsic catalytic properties and to further investigate the tentative reaction mechanisms. This review comprehensively summarizes the very latest advances in the catalytic applications of the Au nanoclusters for the C−C cross-coupling reactions, e.g., Ullmann, Sonogashira, Suzuki cross-couplings, and A3−coupling reactions. It is found that the proposed catalytically active sites are associated with the exposure of gold atoms on the surface of the metal core when partial capping organic ligands are selectively detached under the reaction conditions. Finally, the tentative catalytic mechanisms over the ligand-capped Au nanoclusters and the relationship of structure and catalytic performances at the atomic level using computational methods are explored in detail. Full article
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