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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

As a new type of inorganic‐organic hybrid semiconductor, quantum‐confined atomically precise metal nanoclusters (MNCs) have been widely applied in the fields of chemical sensing, optical imaging, biomedicine and catalysis. Herein, we successfully design and fabricate the first example of MNC‐based spin valves (SVs) that exhibit remarkable magnetoresistance (MR) value up to 1.6 % even at room temperature (300 K). The concomitant photoresponse of MNC‐based SVs unambiguously confirms that the spin‐polarized electron transmission takes place across the MNC interlayer. Furthermore, the spin‐dependent transport property of MNC‐based SVs is largely varied by changing the atomic structure of MNCs. Both experimental proofs and quantum chemistry calculations reveal that the atomic structure‐discriminative spin transport behavior is attributed to the distinct spin‐orbit coupling (SOC) effect of MNCs. [ABSTRACT FROM AUTHOR]

Fluorescent supraparticles of gold, silver and copper nanoclusters are synthesized by simply drying of invert emulsions, resulting in a dozen‐fold increase in photoluminescence quantum yield (up to ≈80 %) and a significant improvement in photostability. The inhibition of the ligand twisting during the intramolecular charge transfer is found to be responsible for the enhancement, especially for the gold nanocluster supraparticles. This research provides a general, flexible, and easy method for producing highly luminescent and photostable metal nanocluster‐based materials that promise practical applications in white‐light‐emitting diodes. [ABSTRACT FROM AUTHOR]

It remains challenging to manipulate the nature of photoluminescence as either fluorescence or phosphorescence for a correlated cluster series. In this work, two correlated nanoclusters, Au5Ag11(SR)8(DPPOE)2 and Pt1Ag16(SR)8(DPPOE)2 with comparable structure features, were synthesized and structurally determined. These two alloy nanoclusters displayed distinct photoluminescent nature—the Au5Ag11 nanocluster is fluorescent, whereas the Pt1Ag16 nanocluster is phosphorescent. The decay processes of the excited electrons in these two nanoclusters have been explicitly mapped out by both experimental and theoretical approaches, disclosing the mechanisms of their fluorescence and phosphorescence. Specifically, the metallic compositions of the nanocluster kernels mattered in determining their photoluminescent nature. The results herein provide an intriguing nanomodel that enables us to grasp the origin of photoluminescence at the atomic level, which further paves the way for fabricating novel nanoclusters or cluster‐based nanomaterials with customized photophysical properties. [ABSTRACT FROM AUTHOR]

Monolayer protected Au nanocluster catalysts are known to undergo structural changes during catalytic reactions, including dissociation and migration of ligands onto the support, which strongly affects their activity and stability. To better understand how the nature of ligands influences the catalytic activity of such catalysts, three types of ceria supported Au nanoclusters with different kinds of ligands (thiolates, phosphines and a mixture thereof) have been studied, employing CO oxidation as model reaction. The thiolate‐protected Au25/CeO2 showed significantly higher CO conversion after activation at 250 °C than the cluster catalysts possessing phosphine ligands. Temperature programmed oxidation and in situ infrared spectroscopy revealed that while the phosphine ligands seemed to decompose and free Au surface was exposed, temperatures higher than 250 °C are required to efficiently remove them from the whole catalyst system. Moreover, the presence of residues on the support seemed to have much greater influence on the reactivity than the gold particle size. [ABSTRACT FROM AUTHOR]

Ultrasmall metal nanoclusters (MNCs, <3 nm) have emerged as a novel class of functional nanomaterials. Different from the prosperous development of noble MNCs, the fabrication of non‐noble MNCs remains a major challenge, which greatly curtails the advance of relevant application fields. Herein the authors put forward an in situ synthesis strategy of bismuth nanoclusters (Bi NCs) within carbon nano‐bundles (Bi NCs@CNBs) by simply carbonizing the Bi‐containing metal–organic framework (Bi‐MOF), and deploy it as a Cl− capturing electrode for electrochemical deionization (EDI) towards the relief of global freshwater scarcity. Of note, as a "killing two birds with one stone" strategy, the Bi‐MOF not only makes the in situ formation of Bi NCs possible but also provides a reinforcing "carbon shell" for better electronic conductivity and structural stability. As a result, the Bi NCs@CNB‐based EDI system displays ultrafast desalination (0.52 mg g−1 s−1) with outstanding cycling stability, which is beneficial from the ultrasmall size of the electrode material and cannot be achieved by large‐sized Bi nanoparticle‐based system. This work is interesting because it unprecedentedly introduces ultrasmall MNCs into EDI to manipulate the surface‐controlled Cl− storage for ultrafast EDI, boosting the advances of both non‐noble MNCs and their application in EDI. [ABSTRACT FROM AUTHOR]

Atomically precise metal clusters are attractive as highly efficient catalysts, but suffer from continuous efficiency deactivation in the catalytic process. Here, we report the development of an efficient strategy that enhances catalytic performance by electropolymerization (EP) of metal clusters into hybrid materials. Based on carbazole ligand protection, three polymerized metal‐cluster hybrid materials, namely Poly‐Cu14cba, Poly‐Cu6Au6cbz and Poly‐Cu6Ag4cbz, were prepared. Compared with isolated metal clusters, metal clusters immobilizing on a biscarbazole network after EP significantly improved their electron‐transfer ability and long‐term recyclability, resulting in higher catalytic performance. As a proof‐of‐concept, Poly‐Cu14cba was evaluated as an electrocatalyst for reducing nitrate (NO3−) to ammonia (NH3), which exhibited ≈4‐fold NH3 yield rate and ≈2‐fold Faraday efficiency enhancement compared to that of Cu14cba with good durability. Similarly, Poly‐Cu6Au6cbz showed 10 times higher photocatalytic efficiency towards chemical warfare simulants degradation than the cluster counterpart. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Metal nanoclusters have attracted much attention due to their ultra‐small size and unique properties. The integration of protein or peptide can bring a synergistic effect on the physicochemical and physiological properties of metal clusters. Metal nanoclusters protected by peptides or proteins exhibit excellent biocompatibility and better disease therapeutic effects. We focus on developing new metal nanoclusters and exploring their therapeutic mechanism, including inhibiting enzyme activity, mitochondrial dysfunction, DNA strand break, and block of the signal pathway. What is the most favorite and original chemistry developed in your research group? The most favorite and original work we have done is the development of gold nanoclusters for diagnostic and therapeutic application. How do you get into this specific field? Could you please share some experiences with our readers? I have a great passion for research on bioanalytical imaging and the biomedical effects of nanomaterials, which may contribute to early diagnosis and treatment of diseases. My research is focused on exploring the mechanism of protein or peptide‐protected metal nanoclusters in disease diagnosis and treatment with the expectation of leading to superior therapeutic outcomes. What is the most important personality for scientific research? In my opinion, respect for originality, bold imagination, and innovation are the most important qualities of scientific research. What is your favorite journal(s)? My favorite journal is Nature Nanotechnology, where we can see the top and latest research progress on nanomaterials and learn about the superiority of nanomaterials and their potential for development. What are your hobbies? I love classical culture, poetry, the beauty of the mood. I also like history, and enjoy visiting historical places to appreciate the local customs. If you have anything else to tell our readers, please feel free to do so. I hope that people who have just started independent research work will not rush for quick success, plan your own direction systematically from the long‐term development. Never go flat, but keep "climbing". [ABSTRACT FROM AUTHOR]

Atomically precise monolayer‐protected metal clusters (nanoclusters) are currently in the focus of interest due to their strongly size‐dependent properties, which gives rise to different applications, and the possibility to study the evolution of structure as a function of size. The use of truly monodisperse metal clusters as building blocks for the preparation of hierarchical structures offers exciting possibilities for the design of new materials. In this overview article we describe the current state of the art in the field of assembly of nanoclusters in one, two and three dimensions. The nanoclusters show rich chemistry that can be used for their assembly. Several reports indicate that, within the assemblies of clusters, their photoluminescence is enhanced. Although there is already a considerable body of reports on the assembly of nanoclusters, we believe that much more exciting properties of nanocluster assemblies will be discovered in the future. [ABSTRACT FROM AUTHOR]

Metal nanoclusters (NCs) have recently attracted great interest in biomedical applications due to their ultrasmall size, good biocompatibility, and unique molecule‐like physical and chemical properties. Metal NCs can be rationally designed and integrated with various targeting moieties to achieve unique physicochemical properties and functions. For therapeutic applications, these multifunctional surface‐modified NCs can provide distinctive advantages over native metal NCs, such as improved therapeutic effects and reduced side effects. In this review, the design principles of targeting strategies for metal NCs and their composites, including passive and active targeting, and physical and chemical targeting are first discussed. The authors then focus on the recent achievements in the application of metal NCs in targeted therapeutics, including chemotherapy, phototherapy, and radiotherapy. Finally, the authors' perspectives on the challenges and opportunities of developing metal NCs in targeted therapeutics, further paving their way for potential clinical applications are provided. [ABSTRACT FROM AUTHOR]

We present a method for atomically precise nanocluster synthesis. As an illustration, we introduced the reducing‐ligand induction combined method and synthesized a novel nanocluster, which was determined to be Au28(SCH2Ph‐tBu)22 with the same number of gold atoms as existing Au28(SR)20 nanoclusters but different ligands (hetero‐composition‐homo‐size). Compared with the latter, the former has distinct properties and structures. In particular, a novel kernel evolution pattern is reported, i.e. the quasi‐linear growth of Au4‐tetrahedron by sharing one vertex and structural features, including a tritetrahedron kernel with two bridging thiolates and two Au6(SCH2Ph‐tBu)6 hexamer chair‐like rings on the kernel surface were also first reported, which endow Au28(SCH2Ph‐tBu)22 with the best photoluminescence quantum yield among hydrophobic thiolated gold nanoclusters so far, probably due to the enhanced charge transfer from the bi‐ring to the kernel via Au−Au bonds. [ABSTRACT FROM AUTHOR]

We present a method for atomically precise nanocluster synthesis. As an illustration, we introduced the reducing‐ligand induction combined method and synthesized a novel nanocluster, which was determined to be Au28(SCH2Ph‐tBu)22 with the same number of gold atoms as existing Au28(SR)20 nanoclusters but different ligands (hetero‐composition‐homo‐size). Compared with the latter, the former has distinct properties and structures. In particular, a novel kernel evolution pattern is reported, i.e., the quasi‐linear growth of Au4‐tetrahedron by sharing one vertex and structural features, including a tritetrahedron kernel with two bridging thiolates and two Au6(SCH2Ph‐tBu)6 hexamer chair‐like rings on the kernel surface were also first reported, which endow Au28(SCH2Ph‐tBu)22 with the best photoluminescence quantum yield among hydrophobic thiolated gold nanoclusters so far, probably due to the enhanced charge transfer from the bi‐ring to the kernel via Au−Au bonds. [ABSTRACT FROM AUTHOR]

During the last few decades, noble metal nanoclusters (NCs) have become an exciting building block in the field of nanoscience. With their ultrasmall size that ranges between 1 and 2 nm, NCs fill the gap between atoms and nanoparticles (NPs), and they show significantly different physicochemical properties compared to their bulk counterparts, such as molecule‐like HOMO‐LUMO discrete electronic transitions, photoluminescence, etc. These properties made NCs potential candidates in various applications, including catalysis, chemical/bioimaging, biomedicine, sensing, and energy conversion. Controlling the size of NPs, which usually exhibit a degree of polydispersity, has been a significant challenge for nano‐scientists. However, metal NCs with atomic precision pave the way to accurately fabricate NPs based on an atom‐by‐atom assembly. This Perspective is directed to the community of nano‐scientists interested in the field of NCs and summarizes the most commonly used synthetic routes of atomically precise metal NCs. Moreover, this Perspective provides an understanding of the different techniques used to control the size of metal NCs with insights on switching the surface ligands from phosphine to thiol. This Perspective also explains the role of physicochemical parameters in different synthetic routes such as high‐temperature route, CO‐directed route, solid‐state route, ligand‐exchange‐induced size/structure transformation (LEIST), etc. We finally give a brief outlook on future challenges of currently used synthetic routes with some suggestions to improve them. [ABSTRACT FROM AUTHOR]

The feasibility to synthesize the ligand‐protected atomically precise nanoclusters with various compositions in sub‐nanometer range (≤2 nm) and the determination of their structures is an important step in long‐pursuit of well‐defined heterogeneous catalysis. Such types of precise catalysts provide an opportunity to understand the fundamentals of catalysis better in terms of: 1) activity and selectivity by metal‐core and metal‐ligand interface, 2) size‐dependent activity, 3) reaction mechanism and 4) active‐site identification and activation. It motivated us to develop the novel metal nanoclusters with precise structures as the new catalytic systems, which led to the several significant findings on above mentioned points. We consider that with this gained knowledge, the future research is expected to bring more exciting advancement in deep understanding of the reaction mechanism, specific‐site identification and tailoring of catalytic active sites at atomic level. [ABSTRACT FROM AUTHOR]

A novel strategy is reported for the synthesis of glutathione (GSH)‐protected bimetallic nanoclusters, Au‐AgNCs@GSH, and its fabrication with polyvinyl alcohol (PVA) into a film sensor for H2S gas detection. Meanwhile, carbon dots (CDs) synthesized from polyethyleneimine (PEI) are introduced as an internal standard to correct the photobleaching of Au‐AgNCs@GSH and uniformity of film. The joining of it greatly improves the chemical and structural stability of the composite film via multi cross‐linking between PEI, PVA, and GSH. The PVA‐AuAgNCs‐CDs film exhibits an emission‐quenching response to H2S gas at atmosphere, which is highly repeatable, fast, sensitive, and can distinguish H2S from other poisonous gases. Finally, the in‐depth mechanism investigations reveal that the quenching response is attributed to decomposition of Au‐AgNCs@GSH and the formation of Au2S and Ag2S in the composite film. As a sensor, the PVA‐supported film combines the functions of fluorescent metal nanoclusters and polymer CDs, providing a portable device for the rapid detection of H2S gas in air. [ABSTRACT FROM AUTHOR]

Metal nanoclusters (NCs) have a particle size of about one nanometer, which makes them the smallest unit that can give a function to a substance. In addition, metal NCs possess physical and chemical properties that are different from those of the corresponding bulk metals. Metal NCs with such characteristics are expected to be important for use in nanotechnology. Research on the precise synthesis of metal NCs and elucidation of their physical/chemical properties and functions is being actively conducted. When metal NCs are alloyed, it is possible to obtain further various electronic and geometrical structures and functions. Thus, research on alloy NCs has become a hot topic in the study of metal NCs and the number of publications on alloy NCs has increased explosively in recent years. Such publications have provided much insight into the effects of alloying on the electronic structure and function of metal NCs. However, the rapid increase in knowledge has made it difficult for researchers (especially those new to the field) to grasp all of it. Therefore, in this review, we summarize the reported chemical composition, geometrical structure, electronic structure, and physical and chemical properties of Aun−xMx(SR)m, Agn−xMx(SR)m, Aun−xMx(PR3)l(SR)m, and Agn−xMx(PR3)l(SR)m (Au=gold, Ag=silver, M=heteroatom, PR3=phosphine, and SR=thiolate) NCs. This review is expected to help researchers understand the characteristics of alloy NCs and lead to clear design guidelines to develop new alloy NCs with intended functions. [ABSTRACT FROM AUTHOR]

Understanding the thermal aggregation behavior of metal atoms is important for the synthesis of supported metal clusters. Here, derived from a metal–organic framework encapsulating a trinuclear FeIII2FeII complex (denoted as Fe3) within the channels, a well‐defined nitrogen‐doped carbon layer is fabricated as an ideal support for stabilizing the generated iron nanoclusters. Atomic replacement of FeII by other metal(II) ions (e.g. ZnII/CoII) via synthesizing isostructural trinuclear‐complex precursors (Fe2Zn/Fe2Co), namely the "heteroatom modulator approach", is inhibiting the aggregation of Fe atoms toward nanoclusters with formation of a stable iron dimer in an optimal metal–nitrogen moiety, clearly identified by direct transmission electron microscopy and X‐ray absorption fine structure analysis. The supported iron dimer, serving as cooperative metal–metal site, acts as efficient oxygen evolution catalyst. Our findings offer an atomic insight to guide the future design of ultrasmall metal clusters bearing outstanding catalytic capabilities. [ABSTRACT FROM AUTHOR]

Aggregation‐induced emission (AIE) provides an efficient strategy to synthesize highly luminescent metal nanoclusters (NCs), however, rational control of emission energy and intensity of metal NCs is still challenging. This communication reveals the impact of surface AuI‐thiolate motifs on the AIE properties of Au NCs, by employing a series of water‐soluble glutathione (GSH)‐coordinated Au complexes and NCs as a model ([Au10SR10], [Au15SR13], [Au18SR14], and [Au25SR18]−, SR=thiolate ligand). Spectroscopic investigations show that the emission wavelength of Au NCs is adjustable from visible to the near‐infrared II (NIR‐II) region by controlling the length of the AuI‐SR motifs on the NC surface. Decreasing the length of AuI‐SR motifs also changes the origin of cluster luminescence from AIE‐type phosphorescence to Au0‐core‐dictated fluorescence. This effect becomes more prominent when the degree of aggregation of Au NCs increases in solution. [ABSTRACT FROM AUTHOR]

Luminescent metal nanoclusters (NCs) are emerging as a new class of functional materials that have rich physicochemical properties and wide potential applications. In recent years, it has been found that some metal NCs undergo aggregation‐induced emission (AIE) and an interesting fluorescence‐to‐phosphorescence (F‐P) switching in solutions. However, insights of both the AIE and the F‐P switching remain largely unknown. Now, gelation of water soluble, atomically precise Ag9 NCs is achieved by the addition of antisolvent. Self‐assembly of Ag9 NCs into entangled fibers was confirmed, during which AIE was observed together with an F‐P switching occurring within a narrow time scale. Structural evaluation indicates the fibers are highly ordered. The self‐assembly of Ag9 NCs and their photoluminescent property are thermally reversible, making the metal–organic gels good candidates for luminescent ratiometric thermometers. [ABSTRACT FROM AUTHOR]

Protein‐protected metal nanoclusters (MNCs), typically consisting of several to a hundred metal atoms with a protein outer layer used for protecting clusters from aggregation, are excellent fluorescent labels for biomedical applications due to their extraordinary photoluminescence, facile synthesis and good biocompatibility. Interestingly, many protein‐protected MNCs have also been reported to exhibit intrinsic enzyme‐like activities, namely peroxidase, oxidase and catalase activities, and are consequently used for biological analysis and environmental treatment. These findings have extended the horizon of protein‐protected MNCs' properties as well as their application in various fields. Furthermore, in the field of nanozymes, protein‐protected MNCs have emerged as an outstanding new addition. Due to their ultra‐small size (<2 nm), they usually have higher catalytic activity, more suitable size for in vivo application, better biocompatibility and photoluminescence in comparison with large size nanozymes. In this review, we will systematically introduce the significant advances in this field and critically discuss the challenges that lie ahead. Ultra‐small nanozymes based on protein‐protected MNCs are on the verge of attracting great interest across various disciplines and will stimulate research in the fields of nanotechnology and biology. This article is characterized under:Therapeutic Approaches and Drug Discovery > Emerging TechnologiesBiology‐Inspired Nanomaterials > Protein and Virus‐Based Structures [ABSTRACT FROM AUTHOR]

Electrospray ionization mass spectrometry (ESI‐MS) is an analytical technique that measures the mass of a sample through "soft" ionization. Recent years have witnessed a rapid growth of its application in noble‐metal nanocluster (NC) analysis. ESI‐MS is able to provide the mass of a noble‐metal NC analyte for the analysis of their composition (n, m, q values in a general formula [MnLm]q), which is crucial in understanding their properties. This review attempts to present various developed techniques for the determination of the composition of noble metal NCs by ESI‐MS. Additionally, advanced applications that use ESI‐MS to further understand the reaction mechanism, complexation behavior, and structure of noble metal NCs are introduced. From the comprehensive applications of ESI‐MS on noble‐metal NCs, more possibilities in nanochemistry can be opened up by this powerful technique. [ABSTRACT FROM AUTHOR]

Aurophilic interactions (AuI⋅⋅⋅AuI) are crucial in directing the supramolecular self‐assembly of many gold(I) compounds; however, this intriguing chemistry has been rarely explored for the self‐assembly of nanoscale building blocks. Herein, we report on studies on aurophilic interactions in the structure‐directed self‐assembly of ultrasmall gold nanoparticles or nanoclusters (NCs, <2 nm) using [Au25(SR)18]− (SR=thiolate ligand) as a model cluster. The self‐assembly of NCs is initiated by surface‐motif reconstruction of [Au25(SR)18]− from short SR‐[AuI‐SR]2 units to long SR‐[AuI‐SR]x (x>2) staples accompanied by structure modification of the intrinsic Au13 kernel. Such motif reconstruction increases the content of AuI species in the protecting shell of Au NCs, providing the structural basis for directed aurophilic interactions, which promote the self‐assembly of Au NCs into well‐defined nanoribbons in solution. More interestingly, the compact structure and effective aurophilic interactions in the nanoribbons significantly enhance the luminescence intensity of Au NCs with an absolute quantum yield of 6.2 % at room temperature. [ABSTRACT FROM AUTHOR]

Metal nanoclusters (NCs) are considered ideal nanomaterials for biological applications owing to their strong photoluminescence (PL), excellent photostability, and good biocompatibility. This study presents a simple and versatile strategy to design proteins, via incorporation of a di‐histidine cluster coordination site, for the sustainable synthesis and stabilization of metal NCs with different metal composition. The resulting protein‐stabilized metal NCs (Prot‐NCs) of gold, silver, and copper are highly photoluminescent and photostable, have a long shelf life, and are stable under physiological conditions. The biocompatibility of the clusters was demonstrated in cell cultures in which Prot‐NCs showed efficient cell internalization without affecting cell viability or losing luminescence. Moreover, the approach is translatable to other proteins to obtain Prot‐NCs for various biomedical applications such as cell imaging or labeling. [ABSTRACT FROM AUTHOR]

A sustainable future demands innovative breakthroughs in science and technology today, especially in the energy sector. Earth‐abundant resources can be explored and used to develop renewable and sustainable resources of energy to meet the ever‐increasing global energy demand. Efficient solar‐powered conversion systems exploiting inexpensive and robust catalytic materials for the photo‐ and photo‐electro‐catalytic water splitting, photovoltaic cells, fuel cells, and usage of waste products (such as CO2) as chemical fuels are appealing solutions. Many electrocatalysts and nanomaterials have been extensively studied in this regard. Low overpotentials, catalytic stability, and accessibility remain major challenges. Metal nanoclusters (NCs, ≤3 nm) with dimensions between molecule and nanoparticles (NPs) are innovative materials in catalysis. They behave like a "superatom" with exciting size‐ and facet‐dependent properties and dynamic intrinsic characteristics. Being an emerging field in recent scientific endeavors, metal NCs are believed to replace the natural photosystem II for the generation of green electrons in a viable way to facilitate the challenging catalytic processes in energy‐conversion schemes. This Review aims to discuss metal NCs in terms of their unique physicochemical properties, possible synthetic approaches by wet chemistry, and various applications (mostly recent advances in the electrochemical and photo‐electrochemical water splitting cycle and the oxygen reduction reaction in fuel cells). Moreover, the significant role that MNCs play in dye‐sensitized solar cells and nanoarrays as a light‐harvesting antenna, the electrochemical reduction of CO2 into fuels, and concluding remarks about the present and future perspectives of MNCs in the frontiers of surface science are also critically reviewed. [ABSTRACT FROM AUTHOR]

A deep understanding on the luminescence property of aggregation‐induced emission (AIE) featured metal nanoclusters (NCs) is highly desired. This paper reports a systematic study on enhancing the luminescence of AIE‐featured Au NCs, which is achieved by Ag doping to engineer the size/structure and aggregation states of the AuI‐thiolate motifs in the NC shell. Moreover, by prolonging the reaction time, the luminescence of the as‐synthesized AuAg NCs could be further tailored from orange to red, which is also due to the variation of the AuI‐thiolate motifs of NCs. This study can facilitate a better understanding of this AIE‐featured luminescent probe and the design of other synthetic routes for this rising family of functional materials. AIE‐featured metal nanoclusters (NCs): The luminescence of AIE‐featured Au NCs could be tailored (e.g. luminescence enhancement and red shift) by Ag doping to engineer the size/structure and aggregation states of the NC shell of AuI‐thiolate motifs. [ABSTRACT FROM AUTHOR]

Graphene‐based nanohybrid is considered to be the most promising nanomaterial for electrochemical sensing applications due to the defects created on the graphene oxide layers. These defects provide graphene oxide unique properties, such as excellent conductivity, large specific surface area, and electrocatalytic activity. These unique properties encourage scientists to develop novel graphene‐based nanohybrids and improve the sensing efficiency. This review, therefore, addresses this topic by comprehensively discussing the strategies to fabricate novel graphene based nanohybrids with high sensitivity. The combinations of graphene with various nanomaterials, such as metal nanoclusters, metal compound nanoparticles, carbon materials, polymers and peptides, in the direction of electrochemical sensing, were systematically analyzed. Meanwhile, the challenges in the functional design and application of graphene‐based nanohybrids were described and the reasonable solutions were proposed. This review provides recent advances of novel graphene‐based nanohybrids for electrochemical sensing by establishing interconnections between graphene and nanomaterials, thus yielding nanohybrids with metal nanoclusters, metal compound nanoparticles, carbon materials, polymers and peptides. In this Perspective, the challenges faced by the graphene‐based nanohybrids as electrochemical sensors are described. [ABSTRACT FROM AUTHOR]

Room‐temperature sodium–sulfur (RT‐Na/S) batteries hold significant promise for large‐scale application because of low cost of both sodium and sulfur. However, the dissolution of polysulfides into the electrolyte limits practical application. Now, the design and testing of a new class of sulfur hosts as transition‐metal (Fe, Cu, and Ni) nanoclusters (ca. 1.2 nm) wreathed on hollow carbon nanospheres (S@M‐HC) for RT‐Na/S batteries is reported. A chemical couple between the metal nanoclusters and sulfur is hypothesized to assist in immobilization of sulfur and to enhance conductivity and activity. S@Fe‐HC exhibited an unprecedented reversible capacity of 394 mAh g−1 despite 1000 cycles at 100 mA g−1, together with a rate capability of 220 mAh g−1 at a high current density of 5 A g−1. DFT calculations underscore that these metal nanoclusters serve as electrocatalysts to rapidly reduce Na2S4 into short‐chain sulfides and thereby obviate the shuttle effect. Enhancing sulfur: Transition‐metal nanoclusters (ca. 1.2 nm) wreathed on hollow carbon nanospheres as S hosts were applied to enhance conductivity and activity of sulfur. These nanoclusters chemisorb the resultant polysulfide and electrocatalyze these into short‐chain sulfides, thus achieving excellent cycling stability and rate performance for room‐temperature sodium–sulfur batteries. [ABSTRACT FROM AUTHOR]

Keywords: metal nanoclusters; nitrobenzene sensing; photoluminescence; silver-based coordination polymers; silver cluster-assembled materials EN metal nanoclusters nitrobenzene sensing photoluminescence silver-based coordination polymers silver cluster-assembled materials 1 1 1 09/05/23 20230901 NES 230901 B Luminescent silver cluster-based coordination polymers b composed of Ag SB 10 sb or Ag SB 12 sb cluster cores and multidentate pyridine linkers were synthesized as well as luminescent polymorphic silver(I)-based coordination polymers. Cover Feature: Five Novel Silver-Based Coordination Polymers as Photoluminescent Sensing Platforms for the Detection of Nitrobenzene (Chem. Eur. J. 49/2023) It was found that these coordination polymers exhibit highly sensitive luminescence quenching effect to nitrobenzene, attributed to the - stacking interactions between the polymers and nitrobenzene as well as the electron-withdrawing character of nitrobenzene. [Extracted from the article]

Homology is well known in organic chemistry; however, it has not yet been reported in nanochemistry. Herein, we introduce the concept of kernel homology to describe the phenomenon of metal nanoclusters sharing the same "functional group" in kernels with some similar properties. To illustrate this point, we synthesized two novel gold nanoclusters, Au44(TBBT)26 and Au48(TBBT)28 (TBBTH=4‐tert‐butylbenzenethiol), and solved their total structures by X‐ray crystallography, which reveals that they have the same Au23 bi‐icosahedron capped with a similar bottom cap (Au6 and Au8, respectively) in the kernels. The two novel gold nanoclusters, together with the existing Au38(PET)24 nanocluster (PETH=phenylethanethiol), have the same "functional group"—Au23—in their kernels and have some similar properties (e.g. electrochemical properties); therefore, they are comparable to the homologues in organic chemistry. Two gold nanoclusters, Au44(TBBT)26 and Au48(TBBT)28 (TBBTH=4‐tert‐butylbenzenethiol), were synthesized and their total structures solved. The two gold nanoclusters, together with the existing Au38(PET)24 nanocluster (PETH=phenylethanethiol), have the same "functional group" (Au23) in their kernels and have some similar (electrochemical) properties; therefore, they are comparable to the homologues in organic chemistry. [ABSTRACT FROM AUTHOR]

Abstract: The redox units of polyaniline (PAni) are used cooperatively, and in situ, to assemble ruthenium (Ru) nanoclusters in a hierarchically ordered carbon electrode. The oxidized quinonoid imine (QI) units in PAni bond Ru complex ions selectively, whereas reduced benzenoid amine (BA) units cannot. By electrochemically tuning the ratio of QI to BA, Ru complexes are spatially confined in the outer layer of hierarchical PAni frameworks. Carbonization of Ru‐PAni hybrids induces nucleation on the outer surface of the carbon support, generating nearly monodisperse Ru nanoclusters. The optimized catalyst has a low loading of approximately 2 wt % Ru, but exhibits a mass activity for the hydrogen evolution reaction that is about 6.8 times better than commercial 20 wt % Pt/C catalyst. [ABSTRACT FROM AUTHOR]

In this paper, an innovative and facile one-pot method for synthesizing water-soluble and stable fluorescent Cu nanoclusters (CuNCs), in which glutathione (GSH) served as protecting ligand and ascorbic acid (AA) as reducing agent was reported. The resultant CuNCs emitted blue-green fluorescence at 440 nm, with a quantum yield (QD) of about 3.08%. In addition, the prepared CuNCs exhibited excellent properties such as good water solubility, photostability and high stability toward high ionic strength. On the basis of the selective quenching of Hg2+ on CuNCs fluorescence, which may be the result of Hg2+ ion-induced aggregation of the CuNCs, the CuNCs was used for the selective and sensitive determination of Hg2+ in aqueous solution. The proposed analytical strategy permitted detection of Hg2+ in a linear range of 4 × 10−8 to 6 × 10−5 M, with a detection limit of 2.2 × 10−8 M. Eventually, the practicability of this sensing approach was confirmed by its successful application to assay Hg2+ in tap water, Lotus lake water and river water samples with the quantitative spike recoveries ranging from 96.9% to 105.4%. [ABSTRACT FROM AUTHOR]

The structure-property correlations of silver nanoclusters (NCs) have rarely been studied, owing to the lack of appropriate materials and the instability of silver NCs. Herein, we show that substituting the central atom of the Ag25(SR)18 NC with another metal atom (i.e. Pd, Pt, or Au) can influence the optical and electrochemical properties. The significant blueshift in optical absorption spectra (compared to Ag25) illustrates the unique electronic perturbation caused by the incorporated heteroatom. In addition, voltammetric measurements were performed to explore the electrochemical properties of Ag NCs for the first time. The O2-O1 potential spacings for different NCs follow the sequence of Pd1Ag24 < Ag25 < Pt1Ag24 < Au1Ag24, and this sequence explains the instability of Ag25 compared to Au1Ag24. Meanwhile, the HOMO-LUMO gaps calculated from differential pulse voltammetry measurements are consistent with those derived from the optical absorption spectra. This study provides further understanding of the structure-property correlations of Ag NCs. [ABSTRACT FROM AUTHOR]

In spite of the successful enhancement of the power-conversion efficiency (PCE) in organic bulk heterojunction (BHJ) solar cells by surface plasmon resonance (SPR), the incorporation of several tens of nanometer-sized (25-50 nm) metal nanoparticles (NPs) has some limitations to further enhancing the PCE due to concerns related to possibly transferring nonradiative energy and disturbing the interface morphology. Instead of tens of nanometer-sized metal NPs, here, dodecanethiol stabilized Au nanoclusters (Au:SR, R = the tail of thiolate) with sub-nm-sized Au38 cores are incorporated on inverted BHJ solar cells. Although metal NPs less than 5 nm in size do not show any scattering or electric field enhancement of incident light by SPR effects, the incorporation of emissive Au:SR nanoclusters provides effects that are quite similar to those of tens of nanometer-sized plasmonic metal NPs. Due to effective energy transfer, based on the protoplasmonic fluorescence of Au:SR, the highest performing solar cells fabricated with Au:SR clusters yield a PCE of 9.15%; this value represents an ≈20% increase in the efficiency compared to solar cells without Au:SR nanoclusters. [ABSTRACT FROM AUTHOR]

The formation of metallic layers on ultrathin molecular films via a well-controlled interface is essential for constructing organic nanodevices composed of metal/molecule/metal sandwich junctions. The scanning tunneling microscopy and spectroscopy studies demonstrate that an ultrasharp metal/molecule interface is realizable by depositing size-selected Ag nanoclusters (Ag n) from the gas phase on few-layer films of C60 molecules. It is also demonstrated that Ag n nanoclusters can be immobilized on monolayer films of oligothiophene molecules via C60 molecules, although they three-dimensionally aggregate on bare oligothiophene films. It is also shown that electrons and holes are injected into the topmost layer of C60 films via the Ag n/C60 interface. Moreover, the barrier height for carrier injection at the Ag n/C60 interface can be modified depending on the size of Ag n nanoclusters and the kinetic energy during the deposition. The present results demonstrate that the controlled immobilization of metallic nanoclusters on molecular films can be used as a fabrication technology for metal/molecule/metal junctions. [ABSTRACT FROM AUTHOR]