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Circularly polarized light (CPL) detection is of great significance in various applications such as drug identification, sensing and imaging. Atomically precise chiral metal nanoclusters with intense circular dichroism (CD) signals are promising candidates for CPL detection, which can further facilitate device miniaturization and integration. Herein, we report the preparation of a pair of optically active chiral silver nanoclusters [Ag7(R/S‐DMA)2(dpppy)3] (BF4)3 (R/S‐Ag7) for direct CPL detection. The crystal structure and molecular formula of R/S‐Ag7 clusters are confirmed by single‐crystal X‐ray diffraction and high‐resolution mass spectrometry. R/S‐Ag7 clusters exhibit strong CD spectra and CPL both in solution and solid states. When used as the photoactive materials in photodetectors, R/S‐Ag7 enables effective discrimination between left‐handed circularly polarized and right‐handed circularly polarized light at 520 nm with short response time, high responsivity and considerable discrimination ratio. This study is the first report on using atomically precise chiral metal nanoclusters for CPL detection. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), known for their extensive porosity and versatile crystallinity, play a crucial role in the development of advanced energy storage materials. However, their application is limited by stability and conductivity issues. This study addresses these challenges by integrating ultrasmall metal nanoclusters, specifically Au4Cu2 NC, synthesized using a mixed ligand strategy combining 2, 4‐Dimethyl benzene thiol (2,4‐DMBTH) and 1,2‐bis(diphenylphosphino)ethane (dppe). The bimetallic Au4Cu2 NC, characterized by Single Crystal X‐Ray Diffraction (SCXRD), is applied to zeolitic imidazolate framework‐8 (ZIF‐8) using both in situ and ex situ methods to explore their electrochemical and physicochemical properties in energy storage. The in situ Au4Cu2 NC/ZIF‐8 composite demonstrated a specific capacitance that is almost two times higher than its ex situ counterpart, attributed to homogeneous dispersion and hence enhanced conductivity. This in situ integration of atomically precise bimetallic nanoclusters on MOFs significantly boosts supercapacitor performance, offering a more effective and reliable solution for energy storage. Further, in practical applications, this device demonstrated an energy density of 87.2 Wh kg−1 at a power density of 1474 W kg−1, highlighting its robustness and potential for high‐performance energy storage applications. This approach effectively combats the issue of nanocluster aggregation on substrates, marking a significant progression in supercapacitor technology. [ABSTRACT FROM AUTHOR]

Alloying is an effective method for modulating metal nanoclusters to enrich their structural diversity and physicochemical properties. Recent investigations have demonstrated that polyoxometalates (POMs) can act as effective multidentate ligands for silver (Ag) nanoclusters to endow them with synergistic properties, reactivity, catalytic properties, and stability. However, the application of POMs as ligands has been confined predominantly to monometallic nanoclusters. Herein, we report a synthetic method for fabricating surface‐exposed gold (Au)−Ag alloy nanoclusters within a ring‐shaped POM ([P8W48O184]40−). Reacting an Ag nanocluster stabilized by the ring‐shaped POM with Au ions (Au+) was found to substitute several Ag atoms at the core of the nanocluster with Au atoms. The resultant {Au8Ag26} alloy nanocluster demonstrated superior photocatalytic activity and stability compared to the pristine Ag nanocluster in the aerobic oxidation of α‐terpinene under visible‐light irradiation. These findings provide fundamental insights into the formation and catalytic properties of POM‐stabilized alloy nanoclusters and advance exploration into the synthesis and applications of diverse metal nanoclusters. [ABSTRACT FROM AUTHOR]

Metal nanoclusters exhibit fascinating molecule-like properties owing to their magic size lying between the small molecules and nanoparticles. This review systematically summarizes their molecule-like properties, including inherent chirality, isomerization, total synthesis, molecular-like optical properties, and DNA-like helical assemblies. Perspectives on future fundamental importance and practical value are also discussed. [Display omitted] Few- to hundred-atom-composed metal nanoclusters (NCs) lie in the transition regime between molecular- and nanometer-scales and have attracted intensive attention for their emerging molecule-like properties that energetically serve various sectors of applications. We here deploy this review in a novel viewpoint, namely the emphasis on the diverse molecule-like properties of metal NCs. We start to clarify the uniqueness in size, precision in total structure, and diversity in species of the molecularly pure metal NCs. This poses the origin of their molecule-like performances. Specifically, it in sequence involves the reminiscent concepts coined in molecular science (i.e., chirality, isomerization, and total synthesis); the most impressive molecule-like optical properties; the emergence of DNA-like helical ensembles mimicking biomolecules and their assemblies. We also provide our perspectives on future molecule-like NCs research, focusing on their fundamental importance and practical value. This review is expected to provide a brand-new viewpoint to revisit the science of metal NCs, by deepening the concept of the metallic molecule and admiring the molecule-like features of metal NCs, which may feed the new vitality and flavors to the various sections of fundamentals and applications in the future. [ABSTRACT FROM AUTHOR]

The prevalence of major bacterial infections has emerged as a significant menace to human health and life. Conventional treatment methods primarily rely on antibiotic therapy, but the overuse of these drugs has led to a decline in their efficacy. Moreover, bacteria have developed resistance towards antibiotics, giving rise to the emergence of superbugs. Consequently, there is an urgent need for novel antibacterial agents or alternative strategies to combat bacterial infections. Nanoantibiotics encompass a class of nano-antibacterial materials that possess inherent antimicrobial activity or can serve as carriers to enhance drug delivery efficiency and safety. In recent years, metal nanoclusters (M NCs) have gained prominence in the field of nanoantibiotics due to their ultra-small size (less than 3 nm) and distinctive electronic and optical properties, as well as their biosafety features. In this review, we discuss the recent progress of M NCs as a new generation of antibacterial agents. First, the main synthesis methods and characteristics of M NCs are presented. Then, we focus on reviewing various strategies for detecting and treating pathogenic bacterial infections using M NCs, summarizing the antibacterial effects of these nanoantibiotics on wound infections, biofilms, and oral infections. Finally, we propose a perspective on the remaining challenges and future developments of M NCs for bacterial infectious therapy. [ABSTRACT FROM AUTHOR]

Despite the remarkable progress made on intercluster conversion in atomically precise metal nanoclusters (MNCs) and their self‐organization to develop microscopic molecular architecture with well‐defined size and shape, achieving light‐induced reversible structural transformation and the development of micro‐ring self‐assembly in MNCs have, so far, remained elusive. The present investigation touches on these two long‐standing quests by showcasing a new route, light‐induced Particle‐Assisted Reversible Interconversion (PARI) for the reversible transformation from Face Centered Cubic (FCC) Ag14NCs to Ag7NCs. Our studies reveal that the lack of plasmonic silver nanoparticles (AgNPs) in the system results in the formation of Ag7NCs with metallic kernels having centrosymmetric crystal packing. The molecular self‐organization of Ag7NCs through various non‐covalent interactions such as C−H⋅⋅⋅O, C−H⋅⋅⋅H−C, and C−H⋅⋅⋅π leads to the formation of micro‐ring morphology, a unique molecular architecture in MNCs. The in situ generated AgNPs due to the acceleration of the reaction kinetics by Cu2+ ions facilitate the growth of Ag14NCs with FCC metallic kernel. These two structural units of AgNCs show light‐induced reversible structural transformation which is also associated with the reversible tuning of their spectroscopic and morphological signatures. This PARI‐guided interconversion strategy put forward a most appropriate example of a structure–property relationship in MNCs. [ABSTRACT FROM AUTHOR]

3D porous organic frameworks, which possess the advantages of high surface area and abundant exposed active sites, are considered ideal platforms to accommodate single atoms (SAs) and metal nanoclusters (NCs) in high‐performance catalysts; however, very little research has been conducted in this field. In the present work, a 3D porous organic framework containing Ni1 SAs and Nin NCs is prepared through the metal‐assisted one‐pot polycondensation of tetraaldehyde and hexaaminotriptycene. The single metal sites and metal clusters confined in the 3D space created a favorable micro‐environment that facilitated the activation of chemically inert CO2 molecules, thus promoting the overall photoconversion efficiency and selectivity of CO2 reduction. The 3D‐NiSAs/NiNCs‐POPs, as a CO2 photoreduction catalyst, demonstrated an exceptional CO production rate of 6.24 mmol g−1 h−1, high selectivity of 98%, and excellent stability. The theoretical calculations uncovered that asymmetrical interaction between Ni1 SAs and Nin NCs not only favored the bending of CO2 molecules and reducing the CO2 reduction energy, but also regulated the electronic structure of the catalyst leading to the optimal binding strength of intermediates. [ABSTRACT FROM AUTHOR]

Thiolate-protected atomically precise nanoclusters (NCs) demonstrate a series of unique luminescent characteristics attributed to their various peculiar electronic structures. Therefore, fluorescent NCs present extraordinary practical values in biosensing and bioimaging research fields. Nevertheless, restricted by the types of fluorescent NCs, there are great difficulties in promoting the development of NCs in fluorescent research areas. As a result, it is of significant necessity for researchers to develop new synthetic pathways to produce high-quality fluorescent NCs. According to the analysis about the structural characteristics of fluorescent NCs, some general features like longer motif and higher ligand-to-metal ratio can be found, consistent to some presented regularities in etching reaction. Consequently, in this work, we used Au25(MHA)18 (MHA = 6-mercaptohexanoic acid) as a model nanocluster and utilized the etching reaction to systematically explore etching products and their corresponding luminescent properties. Moreover, we also identified three main reaction processes in the entire etching reaction process, which can generate new metal nanocluster species with various fluorescent properties. Hence, the etching reaction will provide a good platform to produce new luminescent metal NC species. [ABSTRACT FROM AUTHOR]

Photocatalytic oxygen (O2) reduction has been considered a promising method for hydrogen peroxide (H2O2) production. However, the poor visible light harvesting and low-efficient separation and generation of charge carriers of conventional photocatalysts strongly limited their photocatalytic H2O2 generation performance. Herein, we design a highly efficient photocatalyst in this work by marrying luminescent gold-silver nanoclusters (AuAg NCs) to polyethyleneimine (PEI) modified C3N4 (C3N4-PEI). The key design in this work is the utilization of highly luminescent AuAg NCs as photosensitizers to promote the generation and separation of charge carriers of C3N4-PEI, thereby ultimately producing abundant e-for O2 reduction under visible light illumination (λ ≥ 400 nm). As a result, the as-designed photocatalyst (C3N4-PEI-AuAg NCs) exhibits excellent photocatalytic activity with an H2O2 production capability of 82 µM in pure water, which is 3.5 times higher than pristine C3N4 (23 µM). This interesting design provides a paradigm in developing other high-efficient photocatalysts for visiblelight-driven H2O2 production. [ABSTRACT FROM AUTHOR]

Atomically precise metal nanoclusters (NCs) with unique optical properties and abundant catalytic sites are promising in photocatalysis. However, their light‐induced instability and the difficulty of utilizing the photogenerated carriers for photocatalysis pose significant challenges. Here, MAg24 (M=Ag, Pd, Pt, and Au) NCs doped with diverse single heteroatoms have been encapsulated in a metal–organic framework (MOF), UiO‐66‐NH2, affording MAg24@UiO‐66‐NH2. Strikingly, compared with Ag25@UiO‐66‐NH2, the MAg24@UiO‐66‐NH2 doped with heteroatom exhibits much enhanced activity in photocatalytic hydrogen production, among which AuAg24@UiO‐66‐NH2 presents the best activity up to 3.6 mmol g−1 h−1, far superior to all other counterparts. Moreover, they display excellent photocatalytic recyclability and stability. X‐ray photoelectron spectroscopy and ultrafast transient absorption spectroscopy demonstrate that MAg24 NCs encapsulated into the MOF create a favorable charge transfer pathway, similar to a Z‐scheme heterojunction, when exposed to visible light. This promotes charge separation, along with optimized Ag electronic state, which are responsible for the superior activity in photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Metal nanoclusters, created with atomic precision, are an exceptional class of ultrasmall molecule-like functional materials with wide applications in nonlinear nanophotonics. These ultrasmall clusters exhibit intriguing quantum size effects, leading to discrete energy levels and size-dependent optical and electronic properties. The effective integration of nanoclusters in photonic structures can improve their nonlinear optical properties by promoting a stronger light–matter interaction. In this paper, we demonstrate Tamm cavity-induced nonlinear optical characteristics of ligand-protected platinum-17 metal nanoclusters. The spectral tunability of the Tamm resonance mode is explored by controlling parameters, such as the number of bilayers, spacer layer thickness, and metal characteristics. The nanosecond nonlinear optical studies demonstrate excellent nonlinear absorption properties, attributed to the coupling of Tamm plasmons with the nanoclusters. Notably, a switching behavior in the intensity-dependent absorption coefficient is observed at resonant and off-resonant excitations, suggesting potential applications in optical switching and tunable nonlinear filters. [ABSTRACT FROM AUTHOR]

DNA can stabilize silver nanoclusters (AgN-DNAs) whose atomic sizes and diverse fluorescence colors are selected by nucleobase sequence. These programmable nanoclusters hold promise for sensing, bioimaging, and nanophononics. However, DNA's vast sequence space challenges the design and discovery of AgN-DNAs with tailored properties. In particular, AgN-DNAs with bright near-infrared luminescence above 800 nm remain rare, placing limits on their applications for bioimaging in the tissue transparency windows. Here, we present a design method for near-infrared emissive AgN-DNAs. By combining high-throughput experimentation and machine learning with fundamental information from AgN-DNA crystal structures, we distill the salient DNA sequence features that determine AgN-DNA color, for the entire known spectral range of these nanoclusters. A succinct set of nucleobase staple features are predictive of AgN-DNA color. By representing DNA sequences in terms of these motifs, our machine learning models increase the design success for near-infrared emissive AgN-DNAs by 12.3 times as compared to training data, nearly doubling the number of known AgN-DNAs with bright near-infrared luminescence above 800 nm. These results demonstrate how incorporating known structure-property relationships into machine learning models can enhance materials study and design, even for sparse and imbalanced training data.

Exploiting emissive hydrophobic nanoclusters for hydrophilic applications remains a challenge because of photoluminescence (PL) quenching during phase transfer. In addition, the mechanism underlying PL quenching remains unclear. In this study, the PL‐quenching mechanism was examined by analyzing the atomically precise structures and optical properties of a surface‐engineered Ag29 nanocluster with an all‐around‐carboxyl‐functionalized surface. Specifically, phase‐transfer‐triggered PL quenching was justified as molecular decoupling, which directed an unfixed cluster surface and weakened the radiative transition. Furthermore, emission recovery of the quenched nanoclusters was accomplished by using a supramolecular recoupling approach through the glutathione‐addition‐induced aggregation of cluster molecules, wherein the restriction of intracluster motion and intercluster rotation strengthened the radiative transition of the clusters. The results of this work offer a new perspective on structure‐emission correlations for atomically precise nanoclusters and hopefully provide insight into the fabrication of highly emissive cluster‐based nanomaterials for downstream hydrophilic applications. [ABSTRACT FROM AUTHOR]

A general egg white gel-sol strategy for fabrication of highly fluorescent Au, Ag, Cu, and Pt nanoclusters (NCs) and the first example of using Au NCs for assay of nuclease activity and inhibition were described. The Au NCs enabled bright red fluorescence, and the other Ag, Cu, and Pt NCs have highly blue emission. The red-emitting Au NCs were further applied in assay of S1 nuclease activity and inhibition. Free hemin efficiently quenches the emission of Au NCs by photoinduced electron transfer due to the formation of Au NCs-hemin conjugates. However, G-quadruplex/hemin exerts negligible effect on its fluorescence due to no Au NCs-hemin conjugate formed. There are stronger electrostatic repulsion effects between both negatively charged G-quadruplex and Au NCs. Therefore, a novel G-quadruplex/hemin-based Au NCs fluorescent sensor for S1 nuclease was designed. A known G-rich oligonucleotide (ODN) serves as not only substrate for S1 nuclease but also for the construction of G-quadruplex/hemin. The G-rich ODN is hydrolyzed into fragments by S1 nuclease resulting in no G-quadruplex/hemin formation. Therefore, the free hemin quenches Au NCs fluorescence remarkably and the assay of S1 nuclease activity and inhibition has accomplished. Both the fluorescent NCs syntheses and the detection of S1 nuclease are facile and efficient. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of nitrate (NO3RR) to synthesize ammonia (NH3) provides a competitive manner for carbon neutrality and decentralized NH3 synthesis. Atomically precise nanoclusters, as an advantageous platform for investigating the NO3RR mechanisms and actual active sites, remain largely underexplored due to the poor stability. Herein, we report a (NH4)9[Ag9(mba)9] nanoclusters (Ag9 NCs) loaded on Ti3C2 MXene (Ag9/MXene) for highly efficient NO3RR performance towards ambient NH3 synthesis with improved stability in neutral medium. The composite structure of MXene and Ag9 NCs enables a tandem catalysis process for nitrate reduction, significantly increasing the selectivity and FE of NH3. Besides, compared with individual Ag9 NCs, Ag9/MXene has better stability with the current density performed no decay after 108 hours of reaction. This work provides a strategy for improving the catalytic activity and stability of atomically precise metal NCs, expanding the mechanism research and application of metal NCs. [ABSTRACT FROM AUTHOR]

Surface thiolates play important roles in evincing the structures and properties of thiolated metal nanoclusters—one type of recently emerging inorganic-organic hybrids, and thus the thiolate substitution, especially single thiolate substitution, is highly desirable for subtly tailoring the structures and properties of metal nanoclusters. However, such a single-thiolate substituting is challenging, and its influence on the metal-metal and metal-sulfur bonds remains mysterious due to the absence of the single-thiolate-substituted structure. Here, we developed a combined method, concurrently synthesized the single-thiolate-substituted nanocluster and its parent nanocluster, and successfully resolved their structures by single crystal X-ray crystallography, which reveals that the single thiolate substitute has an obvious influence on the metal-metal and metal-sulfur bond lengths although it has no effect on the absorption profile. Interestingly, the metal-metal and metal-sulfur bonds show various thermal extensibility and even the negative thermal expansion phenomena of the Au–S bond were observed in the single-thiolate-substituted nanocluster. The bond length-related stability was also observed. Overall, this study highlights a novel synthesis method and offers novel structural insights and an in-depth structure-property correlation of thiolated metal nanoclusters. [ABSTRACT FROM AUTHOR]

Two-dimensional material rhenium disulfide (ReS 2) has attracted much attention recently as a potential electrochemical catalyst for the Hydrogen Evolution Reaction (HER). The ReS 2 monolayer is found to be catalytically inert. The challenge lies in activating the ReS 2 monolayer to increase HER output. One of the approaches to this lies in depositing small metal clusters on the monolayer. This paper examines the formation and stability of small metal clusters on 1T distorted ReS 2 monolayer using dispersion-corrected Density Functional Theory. Four different kinds of transition metal clusters, viz. Au, Pt, Mo, and Cr are investigated for geometry and binding on the ReS 2 monolayer. HER activity of each type of ReS 2 -supported metal cluster is investigated based on computed free energy. The HER mechanism was investigated for clusters with optimal activity, and it was found that while the ReS 2 monolayer follows the Volmer-Heyrovsky route, for the transition metal cluster decorated ReS 2 , the Volmer-Tafel route is more probable. • ReS 2 basal plane is catalytically inert; therefore, surface activation is required. • ReS 2 monolayer decorated with small clusters of Au, Pt, Mo and Cr are stable. • ReS 2 supported Au, Pt and Mo clusters are HER active, especially Au3, Pt4 and Mo5, but Cr clusters are not. • The clusters on ReS 2 follow a Tafel mechanism, with lower activation barriers than pure ReS 2. [ABSTRACT FROM AUTHOR]

Exploiting emissive hydrophobic nanoclusters for hydrophilic applications remains a challenge because of photoluminescence (PL) quenching during phase transfer. In addition, the mechanism underlying PL quenching remains unclear. In this study, the PL‐quenching mechanism was examined by analyzing the atomically precise structures and optical properties of a surface‐engineered Ag29 nanocluster with an all‐around‐carboxyl‐functionalized surface. Specifically, phase‐transfer‐triggered PL quenching was justified as molecular decoupling, which directed an unfixed cluster surface and weakened the radiative transition. Furthermore, emission recovery of the quenched nanoclusters was accomplished by using a supramolecular recoupling approach through the glutathione‐addition‐induced aggregation of cluster molecules, wherein the restriction of intracluster motion and intercluster rotation strengthened the radiative transition of the clusters. The results of this work offer a new perspective on structure‐emission correlations for atomically precise nanoclusters and hopefully provide insight into the fabrication of highly emissive cluster‐based nanomaterials for downstream hydrophilic applications. [ABSTRACT FROM AUTHOR]

Atomically precise metal nanoclusters (NCs) emerge as fascinating synthons in self‐assembled materials. The self‐assembly of metal NCs are highly sensitive to the environment because they have an inorganic‐organic hybridized structure and a relatively complicated conformation. Here, it is shown that when confined in crowded colloids, a water‐soluble Ag9‐cored nanocluster (Ag9‐NC) can self‐ assemble into ultra‐long (up to millimeters) and photoluminescent ribbons with high flexibility. The ribbon contains rectangularly organized columns of Ag9‐NCs and can undergo secondary self‐assembly to form bundled and branched structures. Formation of ribbons is observed in all the tested colloids, including lyotropic liquid crystals and disordered, three‐dimensional network. The high viscosity/elasticity of the crowded colloids weakens gravity‐induced sedimentation of the ribbons, leading to the formation of an interesting class of inorganic‐organic composite materials where the hard Ag‐containing skeleton strengthens the soft matter. The simultaneously occurring symmetry breaking during the self‐assembly of Ag9‐NCs gives uncontrolled supramolecular chirality, which can be tuned through the majority rule and soldier‐and‐sergeant rule by the introduction of chiral seeds. The regulated chirality and the intrinsic photoluminescence of the Ag9‐NCs ribbons impart the composite material circularly polarized luminescence, opening the door for a variety of potential applications. [ABSTRACT FROM AUTHOR]

Metal nanoclusters (NCs) are stable aggregates at the molecular level, consisting of several to hundreds of metal atoms bound together by physical or chemical interaction. These nanoclusters exhibit unique physicochemical properties that have garnered significant attention in various fields, including biology, catalysis, sensing, and drug delivery. In the field of catalytic reactions, atomically precise metal nanoclusters have acted as an archetypical model for elucidating the structural evolution and structure-property relationship of nanomaterials. However, due to the factors such as the uncertainty of the growth mechanism, the complexity of the crystallization process, and the inherent poor stability, the cluster research faces some challenges in the precise synthesis, structural analysis as well as the comprehension of catalytic reaction mechanism which hinder the full exploration and understanding of these fascinating properties of clusters. Recent years, mass spectrometry (MS) has emerged as a crucial tool in biomolecular analysis and the detection of organic reaction intermediates due to its high sensitivity, high resolution, and fast response. In cluster chemistry, the researchers have also introduced this technique into the study of metal nanoclusters with precise atomic numbers, which have played an important role in the synthesis of clusters and the analysis of their structures as well as reaction mechanisms. The ion source, as the "heart" of the MS, can ionize the analyte and then be detected by MS. Currently, the main ionization methods used for cluster analysis are electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI). These two "soft" ionization techniques can obtain the quasi-molecular ion peaks of the clusters without destroying the structure of the clusters, thus determining the composition of the clusters. In addition, MS enables real-time characterization of the reaction process in solution, allowing for online monitoring of complex reaction components, providing an experimental basis for synthesis processes and catalytic reaction mechanisms of metal clusters. Notably, gas-phase ion-molecule reactions can provide catalytic primitive steps and reaction kinetics enabling in-depth analysis of microscopic reaction mechanisms at a strictly molecular level. For the structural characterization of clusters, tandem mass spectrometry (MS/MS) combined with quantum chemical calculation provides a powerful tool to study and understand the structural evolutions of clusters. By comparing and verifying the experimental and computational results, the correlation between the catalyst structure and its performance can be established, deepening our understanding of the catalytic reaction mechanism and process. This paper was focused on the latest development of soft ionization MS in monitoring intermediates of cluster synthesis, structure analysis, and catalytic reaction mechanism, and the emerging directions in this fascinating area of research were highlighted. [ABSTRACT FROM AUTHOR]

Abstract 3D porous organic frameworks, which possess the advantages of high surface area and abundant exposed active sites, are considered ideal platforms to accommodate single atoms (SAs) and metal nanoclusters (NCs) in high‐performance catalysts; however, very little research has been conducted in this field. In the present work, a 3D porous organic framework containing Ni1 SAs and Nin NCs is prepared through the metal‐assisted one‐pot polycondensation of tetraaldehyde and hexaaminotriptycene. The single metal sites and metal clusters confined in the 3D space created a favorable micro‐environment that facilitated the activation of chemically inert CO2 molecules, thus promoting the overall photoconversion efficiency and selectivity of CO2 reduction. The 3D‐NiSAs/NiNCs‐POPs, as a CO2 photoreduction catalyst, demonstrated an exceptional CO production rate of 6.24 mmol g−1 h−1, high selectivity of 98%, and excellent stability. The theoretical calculations uncovered that asymmetrical interaction between Ni1 SAs and Nin NCs not only favored the bending of CO2 molecules and reducing the CO2 reduction energy, but also regulated the electronic structure of the catalyst leading to the optimal binding strength of intermediates.

Photocatalytic oxygen (O2) reduction has been considered a promising method for hydrogen peroxide (H2O2) production. However, the poor visible light harvesting and low-efficient separation and generation of charge carriers of conventional photocatalysts strongly limited their photocatalytic H2O2 generation performance. Herein, we design a highly efficient photocatalyst in this work by marrying luminescent gold-silver nanoclusters (AuAg NCs) to polyethyleneimine (PEI) modified C3N4 (C3N4-PEI). The key design in this work is the utilization of highly luminescent AuAg NCs as photosensitizers to promote the generation and separation of charge carriers of C3N4-PEI, thereby ultimately producing abundant e− for O2 reduction under visible light illumination (λ ≥ 400 nm). As a result, the as-designed photocatalyst (C3N4-PEI-AuAg NCs) exhibits excellent photocatalytic activity with an H2O2 production capability of 82 μM in pure water, which is 3.5 times higher than pristine C3N4 (23 μM). This interesting design provides a paradigm in developing other high-efficient photocatalysts for visible-light-driven H2O2 production.

DNA as an intriguing organic ligand has been widely employed for synthesizing metal nanoclusters and engineering their properties. This review aims to present recent progress on DNA-encoded metal (Ag, Cu, Au, Ag/Pt, Cu/Ag, etc.) nanoclusters (DNA-MNCs), focusing on their applications in the fields of analysis, logic operation, and therapy based on properties including fluorescence, electrochemiluminescence (ECL), and antibacterial and catalytic activity, and summarizes the attractive features of the latest research. The key points are briefly described as follows. (1) Analytical systems have been constructed based on fluorescence regulation, and nuclease-assisted and enzyme-free amplification strategies have been extensively adopted with fluorescent DNA-MNCs for amplified analysis. (2) DNA-MNCs may play more than one role (emitter, quencher, or catalyst) in ECL-based analytical systems. (3) Apart from antibacterial activity, DNA-MNCs also possess apparent catalytic capability, such as enzyme-like activity (i.e., nanozymes), which has been applied in colorimetric systems. (4) Reversibly regulating the catalytic activity of DNA-MNCs has been attained with DNA systems. It is believed that through in-depth investigation of the relationship between atomic structure and property, more novel DNA-MNCs will be explored and applied in the future.

Abstract Nanomaterials, specifically metal nanoclusters (NCs), are gaining attention as a promising class of antibacterial agents. Metal NCs exhibit antibacterial properties due to their ultrasmall size, extensive surface area, and well-controlled surface ligands. The antibacterial mechanisms of metal NCs are influenced by two primary factors: size and surface charge. In this review, we summarize the impacts of size and surface charge of metal NCs on the antibacterial mechanisms, their interactions with bacteria, and the factors that influence their antibacterial effects against both gram-negative and gram-positive bacteria. Additionally, we highlight the mechanisms that occur when NCs are negatively or positively charged, and provide examples of their applications as antibacterial agents. A better understanding of relationships between antibacterial activity and the properties of metal NCs will aid in the design and synthesis of nanomaterials for the development of effective antibacterial agents against bacterial infections. Based on the remarkable achievements in the design of metal NCs, this review also presents conclusions on current challenges and future perspectives of metal NCs for both fundamental investigations and practical antibacterial applications. Graphical Abstract

Due to the powerful quantum confined space effects and multiple modes of small atomic sizes, metal nanoclusters (NCs) like thiolate-protected noble metals, such as silver (Ag) and gold (Au), which have a core sizes less than 3 nm, have developed a class of "metallic molecules" with multiple optical, magnetic, and electronic properties. To find a well-defined nanocatalysts, especially ligand-passivated metal NCs, great strides have been achieved in the efficient synthesis of atomically precise nanoparticles. Methods of synthesis such as bottom-up growth, top-down approach, ligand engineering, and interconversion system, are mentioned in this overview. Such clearly defined metal NCs have demonstrated considerable promise in catalysis research and have evolved into a distinct class of model catalysts. Focusing on the oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), and oxygen evolution reaction (OER), this article attempts to outline current developments in NCs of molecular metals employed in electrocatalytic reactions. The paper highlights the relationship between the structure and performance of the catalytic mechanism and examines the potential effects of metal cluster sizes, metal core structures, charges, ligands, and metal–ligand binding patterns on their electrocatalytic activity. Future research opportunities and challenges are also proposed.

DNA as an intriguing organic ligand has been widely employed for synthesizing metal nanoclusters and engineering their properties. This review aims to present recent progress on DNA-encoded metal (Ag, Cu, Au, Ag/Pt, Cu/Ag, etc.) nanoclusters (DNA-MNCs), focusing on their applications in the fields of analysis, logic operation, and therapy based on properties including fluorescence, electrochemiluminescence (ECL), and antibacterial and catalytic activity, and summarizes the attractive features of the latest research. The key points are briefly described as follows. (1) Analytical systems have been constructed based on fluorescence regulation, and nuclease-assisted and enzyme-free amplification strategies have been extensively adopted with fluorescent DNA-MNCs for amplified analysis. (2) DNA-MNCs may play more than one role (emitter, quencher, or catalyst) in ECL-based analytical systems. (3) Apart from antibacterial activity, DNA-MNCs also possess apparent catalytic capability, such as enzyme-like activity (i.e., nanozymes), which has been applied in colorimetric systems. (4) Reversibly regulating the catalytic activity of DNA-MNCs has been attained with DNA systems. It is believed that through in-depth investigation of the relationship between atomic structure and property, more novel DNA-MNCs will be explored and applied in the future. [ABSTRACT FROM AUTHOR]

Atomically precise metal nanoclusters (NCs) represent a promising generation of metal nanomaterial because of characteristic atomic stacking mode, abundant catalytic active sites, and molecular-like discrete energy band structure. However, crafting metal NCs-dominated photocatalytic systems with mediated charge transport pathways for photoredox catalysis is in the infant stage and their photocatalytic mechanisms remain elusive, which is largely hampered by the ultra-short charge lifetime, generic instability, and complicated electronic structure of metal NCs. In this study, the smart construction of all-solid-state metal NCs-transition metal chalcogenides quantum dots (TMCs QDs) Z-scheme artificial photosystems for robust and stable solar-to-hydrogen conversion is demonstrated. The concurrent favorable photosensitization efficiency of metal NCs and TMCs QDs synergistically stimulate the unexpected Z-scheme charge transport pathway, which significantly boosts the anisotropic spatial vectorial charge transport/separation, giving rise to considerably enhanced visible-light-responsive photocatalytic hydrogen generation performances along with favorable stability. This study would push forward the prosperity of exploring metal NCs-based photosystems for solar-to-hydrogen conversion. [ABSTRACT FROM AUTHOR]

Nanomaterials, specifically metal nanoclusters (NCs), are gaining attention as a promising class of antibacterial agents. Metal NCs exhibit antibacterial properties due to their ultrasmall size, extensive surface area, and well-controlled surface ligands. The antibacterial mechanisms of metal NCs are influenced by two primary factors: size and surface charge. In this review, we summarize the impacts of size and surface charge of metal NCs on the antibacterial mechanisms, their interactions with bacteria, and the factors that influence their antibacterial effects against both gram-negative and gram-positive bacteria. Additionally, we highlight the mechanisms that occur when NCs are negatively or positively charged, and provide examples of their applications as antibacterial agents. A better understanding of relationships between antibacterial activity and the properties of metal NCs will aid in the design and synthesis of nanomaterials for the development of effective antibacterial agents against bacterial infections. Based on the remarkable achievements in the design of metal NCs, this review also presents conclusions on current challenges and future perspectives of metal NCs for both fundamental investigations and practical antibacterial applications. [ABSTRACT FROM AUTHOR]

In the modern development of nanoscience and nanotechnology, metal nanoclusters have emerged as a foremost category of nanomaterials exhibiting remarkable biocompatibility and photo-stability having dramatically distinctive optical, electronic, and chemical properties. This review focuses on synthesizing fluorescent metal nanoclusters in a greener way to make them suitable for biological imaging and drug delivery application. The green methodology is the desired route for sustainable chemical production and should be utilized for any form of chemical synthesis including nanomaterials. It aims to eliminate harmful waste, uses non-toxic solvents, and employs energy-efficient processes for the synthesis. This article provides an overview of conventional synthesis methods, including stabilizing nanoclusters by small organic molecules in organic solvents. Then we focus on the improvement of properties, applications of green synthesized metal nanoclusters, challenges involved, and further advancement required in the direction of green synthesis of MNCs. There are plenty of problems for scientists to solve to make nanoclusters suitable for bio-applications, chemical sensing, and catalysis synthesized by green methods. Using bio-compatible and electron-rich ligands, understanding ligand–metal interfacial interactions, employing more energy-efficient processes, and utilizing bio-inspired templates for synthesis are some immediate problems worth solving in this field that requires continued efforts and interdisciplinary knowledge and collaboration. [ABSTRACT FROM AUTHOR]

Abstract Atomically precise metal nanoclusters (NCs) emerge as fascinating synthons in self‐assembled materials. The self‐assembly of metal NCs are highly sensitive to the environment because they have an inorganic‐organic hybridized structure and a relatively complicated conformation. Here, it is shown that when confined in crowded colloids, a water‐soluble Ag9‐cored nanocluster (Ag9‐NC) can self‐ assemble into ultra‐long (up to millimeters) and photoluminescent ribbons with high flexibility. The ribbon contains rectangularly organized columns of Ag9‐NCs and can undergo secondary self‐assembly to form bundled and branched structures. Formation of ribbons is observed in all the tested colloids, including lyotropic liquid crystals and disordered, three‐dimensional network. The high viscosity/elasticity of the crowded colloids weakens gravity‐induced sedimentation of the ribbons, leading to the formation of an interesting class of inorganic‐organic composite materials where the hard Ag‐containing skeleton strengthens the soft matter. The simultaneously occurring symmetry breaking during the self‐assembly of Ag9‐NCs gives uncontrolled supramolecular chirality, which can be tuned through the majority rule and soldier‐and‐sergeant rule by the introduction of chiral seeds. The regulated chirality and the intrinsic photoluminescence of the Ag9‐NCs ribbons impart the composite material circularly polarized luminescence, opening the door for a variety of potential applications.

Nitrobenzene (NB) is a highly toxic chemical and a cause for concern to human health and the environment. Hence, it is worth designing new efficient and robust sensing platforms for NB. In this study, we present three newly synthesized luminescent silver cluster‐based coordination polymers, {[Ag10(StBu)6(CF3COO)4(hpbt)] (DMAc)2(CH3CN)2}n (hpbt=N,N,N',N'N",N"‐hexa(pyridine‐4‐yl)benzene‐1,3,5‐triamine), [Ag12(StBu)6(CF3COO)6(bpva)3]n (bpva=9,10‐Bis(2‐(pyridin‐4‐yl)vinyl)anthracene), and {[Ag12(StBu)6(CF3COO)6(bpb)(DMAc)2(H2O)2] (DMAc)2}n (bpb=1,4‐Bis(4‐pyridyl)benzene) composed of Ag10, Ag12 and Ag12 cluster cores, respectively, connected by multidentate pyridine linkers. In addition, two new luminescent polymorphic silver(I)‐based coordination polymers, [Ag(CF3COO)(dpa)]n (dpa=9,10‐di(4‐pyridyl)anthracene) referred to as Agdpa (H) and Agdpa (R), where H and R denote hexagon‐ and rod‐like crystal shapes, respectively, have been prepared. The coordination polymers exhibit highly sensitive luminescence quenching effects to NB, attributed to the π−π stacking interactions between the polymers and NB as well as the electron‐withdrawing character of NB. [ABSTRACT FROM AUTHOR]

Luminescence is one of the most important properties for metal nanoclusters; however, clearly revealing its origin remains challenging. The different luminescence properties of the two prototypical 8e nanoclusters Au11 and Au13 remain elusive—Au11 is always nonluminescent, whereas Au13 is luminescent. In this work, by using a designed unique aromatic ligand (quinoline-2-thiol), we obtained new atomically precise phosphine-thiolate-protected neutral Au11-SH and cationic Au13-SH. In comparison with the classic phosphine-halide-protected Au11-Cl and Au13-Cl, the Cl-to-thiol alteration triggered room-temperature luminescence of the Au11 core and dramatically modulated that of the Au13 core. Ultrafast ultraviolet/infrared (UV/IR) spectroscopy, which is sensitive to organic aromatic groups, together with ultrafast transient absorption (TA) spectroscopy unprecedently revealed a relaxation process from the ligand to core state affecting the dynamics in excited states and some critical intermediate states favouring efficient room-temperature emission of these nanoclusters. This work provides some new insights into the origin of photoluminescence of metal nanoclusters and opens an avenue to modulate the dynamics of their excited states using aromatic ligands, which would have direct applications in lighting, light harvesting, and photocatalysis. [ABSTRACT FROM AUTHOR]

After analyzing the problem of extending the Gibbs surface excess method to nanoscale objects, two different approaches to the application of the Gibbs method for finding the specific surface energy of metal nanoparticles are being considered. The first approach involves the use of the local coordination approximation to estimate the specific surface energy of icosahedral FCC metal nanoparticles (magic nanoclusters). For the first time, we have drawn attention to the fact that for such a nanocluster, it is possible to accurately calculate both the fraction of surface atoms and the values of the first coordination number in the inner region of the nanoparticle and on its surface (faces, edges, and vertices). The second approach implemented by us earlier for spherical Au nanoparticles and here for FCC Pt nanoparticles, involves the complex application of the Gibbs method adapted for nanoparticles and the results of molecular dynamics simulation. Estimates using both approaches agree with the experimental values of the surface energy corresponding to the flat surface of the bulk phases of the corresponding metals. In the final section of the work, the limits of applicability of thermodynamics to nanosystems are discussed. [ABSTRACT FROM AUTHOR]

The use of proteins as biomolecular templates to synthesize atomically precise metal nanoclusters has been gaining traction due to their appealing properties such as photoluminescence, good colloidal- and photostability and biocompatibility. The synergistic effect of using a protein scaffold and metal nanoclusters makes it especially attractive for biomedical applications. Unlike other reviews, we focus on proteins in general as the protective ligand for various metal nanoclusters and highlight their applications in the biomedical field. We first introduce the approaches and underlined principles in synthesizing protein-templated metal nanoclusters and summarize some of the typical proteins that have been used thus far. Afterwards, we highlight the key physicochemical properties and the characterization techniques commonly used for the size, structure and optical properties of protein-templated metal nanoclusters. We feature two case studies to illustrate the importance of combining these characterization techniques to elucidate the formation process of protein-templated metal nanoclusters. Lastly, we highlight the promising applications of protein-templated metal nanoclusters in three areas—biosensing, diagnostics and therapeutics. [ABSTRACT FROM AUTHOR]

Dynamic metal nanoclusters have garnered widespread attention due to their unique properties and potential applications in various fields. Researchers have been dedicated to developing new synthesis methods and strategies to control the morphologies, compositions, and structures of metal nanoclusters. Through optimized synthesis methods, it is possible to prepare clusters with precise sizes and shapes, providing a solid foundation for subsequent research. Accurate determination of their crystal structures is crucial for understanding their behavior and designing custom functional materials. Dynamic metal nanoclusters also demonstrate potential applications in catalysis and optoelectronics. By manipulating the sizes, compositions, and surface structures of the clusters, efficient catalysts and optoelectronic materials can be designed and synthesized for various chemical reactions and energy conversion processes. This review summarizes the research progress in the synthesis methods, crystal structure characterization, and potential applications of dynamic metal nanoclusters. Various nanoclusters composed of different metal elements are introduced, and their potential applications in catalysis, optics, electronics, and energy storage are discussed. Additionally, the important role of dynamic metal nanoclusters in materials science and nanotechnology is explored, along with an overview of the future directions and challenges in this field. [ABSTRACT FROM AUTHOR]

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In the past 2 decades, multicolour light‐emissive nanomaterials have gained significant interest in chemical and biological sciences because of their unique optical properties. These materials have drawn much attention due to their unique characteristics towards various application fields. The development of novel nanomaterials has become the pinpoint for different application areas. In this review, the recent progress in the area of multicolour‐emissive nanomaterials is summarized. The different emissions (white, orange, green, red, blue, and multicolour) of nanostructure materials (metal nanoclusters, quantum dots, carbon dots, and rare earth‐based nanomaterials) are briefly discussed. The potential applications of different colour‐emissive nanomaterials in the development of fluorescent inks, light‐emitting diodes, cell imaging, and sensing devices are briefly summarized. Finally, the future perspectives of multicolour‐emissive nanomaterials are discussed. [ABSTRACT FROM AUTHOR]

Atomically precise nanoclusters comprising 1–100 atoms have emerged as a new class of nanomaterials with intriguing size-dependent physicochemical properties. The significant changes in the properties of nanoclusters were observed in tailoring the number of metal atoms and ligands that determines their functions and applicability. Since 1990, thiolated gold nanoclusters have been studied. The separation of monodispersed clusters was crucial and time-consuming. To address these shortcomings, several separation techniques have made it possible to separate the series of metal nanoclusters with a precise composition of metals and ligands. Among these techniques, polyacrylamide gel electrophoresis was utilized for hydrophilic cluster separation. This review shall focus on the principle, operation and application of the polyacrylamide gel electrophoresis technique to encourage a greater understanding of the characteristics and usefulness of this method.

The reckless use of non-replenishable fuels by the growing population for energy and the resultant incessant emissions of hazardous gases and waste products into the atmosphere have insisted that scientists fabricate materials capable of managing these global threats at once. In recent studies, photocatalysis has been employed to focus on utilizing renewable solar energy to initiate chemical processes with the aid of semiconductors and highly selective catalysts. A wide range of nanoparticles has showcased promising photocatalytic properties. Metal nanoclusters (MNCs) with sizes below 2 nm, stabilized by ligands, show discrete energy levels and exhibit unique optoelectronic properties, which are vital to photocatalysis. In this review, we intend to compile information on the synthesis, true nature, and stability of the MNCs decorated with ligands and the varying photocatalytic efficiency of metal NCs concerning changes in the aforementioned domains. The review discusses the photocatalytic activity of atomically precise ligand-protected MNCs and their hybrids in the domain of energy conversion processes such as the photodegradation of dyes, the oxygen evolution reaction (ORR), the hydrogen evolution reaction (HER), and the CO2 reduction reaction (CO2RR). [ABSTRACT FROM AUTHOR]

Single atoms and nanoclusters of Fe, Ni, Co, Cu, and Mn are systematically designed and embedded in a well‐defined C1N1‐type material that has internal cavities of ≈0.6 nm based on four N atoms. These N atoms serve as perfect anchoring points for the nucleation of small nanoclusters of different metal natures through the creation of metal‐nitrogen (TM‐N4) bonds. After pyrolysis at 800 °C, TM@CNx‐type structures are obtained, where TM is the transition metal and x < 1. Fe@CNx and Co@CNx are the most promising for oxygen reduction reaction and hydrogen evolution reaction, respectively, with a Pt‐like performance, and Ni@CNx is the most active for oxygen evolution reaction (OER) with an EOER of 1.59 V versus RHE, far outperforming the commercial IrO2 (EOER = 1.72 V). This systematic and benchmarking study can serve as a basis for the future design of advanced multi‐functional electrocatalysts by modulating and combining the metallic nature of nanoclusters and single atoms. [ABSTRACT FROM AUTHOR]

Abstract—The isomers of Mg24L2 nanoclusters with dopants L from the firt three periods (L = Li–Zn) in the exo- and endohedral positions of the magnesium cage have been calculated by the density functional theory (DFT) method. The effect of dopants on the structure, stability, and position on the energy scale has been studied. For the systems with atoms L = H, Li, Be N, Na, Co, and Cu, the "open" positions of dopants at the surface are more favorable, unlike their analogs with L = Be and B, for which the "closed" positions in the inner cavity of the cluster are more favorable and their promotion to the surface requires a significant energy input. For clusters with O, Si, P, S, and early 3d metal atoms, the differences in the energies of the exo- and endohedral isomers do not exceed a few kcal/mol. The atoms of the second half of the 3d series are characterized by their association into diatomic dopants L2. The results are compared with the data of similar DFT calculations of isomers of Al42L2 aluminum clusters with the same dopants L = Li–Zn and are of interest for modeling the mechanisms of catalytic hydrogenation of magnesium and aluminum nanoclusters at the molecular level. [ABSTRACT FROM AUTHOR]

Abstract Combating bacterial infections is one of the most important applications of nanomedicine. In the past two decades, significant efforts have been committed to tune physicochemical properties of nanomaterials for the development of various novel nanoantibiotics. Among which, metal nanoclusters (NCs) with well-defined ultrasmall size and adjustable surface chemistry are emerging as the next-generation high performance nanoantibiotics. Metal NCs can penetrate bacterial cell envelope more easily than conventional nanomaterials due to their ultrasmall size. Meanwhile, the abundant active sites of the metal NCs help to catalyze the bacterial intracellular biochemical processes, resulting in enhanced antibacterial properties. In this review, we discuss the recent developments in metal NCs as a new generation of antimicrobial agents. Based on a brief introduction to the characteristics of metal NCs, we highlight the general working mechanisms by which metal NCs combating the bacterial infections. We also emphasize central roles of core size, element composition, oxidation state, and surface chemistry of metal NCs in their antimicrobial efficacy. Finally, we present a perspective on the remaining challenges and future developments of metal NCs for antibacterial therapeutics. Graphical Abstract

Atomic‐level manipulation of catalysts is important for both fundamental studies and practical applications. Here, the central metal atom in an atomically precise Ag25 nanocluster (NC) is replaced with a single Pd, Pt, and Au atom, respectively, and employed as a model system to study the structure–property–activity relationship at the atomic level. While the geometric structures are well‐preserved after doping, the electronic structures of Ag25 NCs are significantly altered. The combination of Ag25 and TiO2 enhances the charge separation at the interface, exhibiting a 10 times higher hydrogen production rate in photocatalytic hydrogen evolution reaction compared to bare TiO2. Further results show that heteroatoms doping has a negative impact on performance, particularly in the cases of Pd and Au doping. Ultraviolet photoelectron spectroscopy measurements and density functional theory calculations suggest that the lower activities are due to an energy mismatch between the levels of doped NCs and TiO2. These findings not only reveal the impact of heteroatoms doping on the electronic properties and photocatalytic activities of NCs, but can also guide the design of heterometallic NCs for photocatalytic applications. [ABSTRACT FROM AUTHOR]

Selective detection of Al3+ is of great significance both for the benefit of human health and environmental safety considerations. In this work, a sensitive and selective fluorescence assay for Al3+ was proposed based on the green‐emissive Cu nanoclusters (Cu NCs). Different from the commonly reported works, the green emissive Cu NCs showed dual emission bands at 450 and 510 nm, attributed to the reaction product between polyvinyl pyrrolidone and ascorbic acid and the Cu core, respectively. Al3+ could induce the aggregation of Cu NCs by forming covalent bonds, which results in the enhancement of photoluminescence intensity. This enhancement phenomenon is rather selective to Al3+, which endows the detection in real samples. These results provide new insights for the fluorescence mechanisms of metal NCs, which also provided a functional luminescent material for various applications, such as chemical sensing, bioimaging and photoelectric devices. [ABSTRACT FROM AUTHOR]

Selective detection of Al3+ is of great significance both for the benefit of human health and environmental safety considerations. In this work, a sensitive and selective fluorescence assay for Al3+ was proposed based on the green‐emissive Cu nanoclusters (Cu NCs). Different from the commonly reported works, the green emissive Cu NCs showed dual emission bands at 450 and 510 nm, attributed to the reaction product between polyvinyl pyrrolidone and ascorbic acid and the Cu core, respectively. Al3+ could induce the aggregation of Cu NCs by forming covalent bonds, which results in the enhancement of photoluminescence intensity. This enhancement phenomenon is rather selective to Al3+, which endows the detection in real samples. These results provide new insights for the fluorescence mechanisms of metal NCs, which also provided a functional luminescent material for various applications, such as chemical sensing, bioimaging and photoelectric devices. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE)-type metal nanoclusters (NCs) represent an innovative type of luminescent metal NCs whose aggregates exhibit superior performance over that of individuals, attracting wide attention over the past decade. Here, we give a concise overview of the progress made in this area, from design strategies to applications. The representative design strategies, including solvent-induction, cation-induction, crystallization-induction, pH-induction, ligand inheritance, surface constraint, and minerals- and MOF-confinement, are first discussed. We then present the typical practical applications of AIE-type metal NCs in the various sectors of bioimaging, biological diagnosis and therapy (e.g., antibacterial agents, cancer radiotherapy), light-emitting diodes (LEDs), detection assays, and circularly polarized luminescence (CPL). To this end, we present our viewpoints on the promises and challenges of AIE-type metal NCs, which may shed light on the design of highly luminescent metal NCs, stimulating new vitality and serving as a continuous boom for the metal NC community in the future. [ABSTRACT FROM AUTHOR]