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The production of atomically dispersed metal catalysts remains a significant challenge in the field of heterogeneous catalysis due to coexistence with continuously packed sites such as nanoclusters and nanoparticles. This work presents a comprehensive guidance on how to increase the degree of atomization through a selection of appropriate experimental conditions and supports. It is based on a rigorous macro-kinetic theory that captures relevant competing processes of nucleation and formation of single atoms stabilized by point defects. The effects of metal-support interactions and deposition parameters on the resulting single atom to nanocluster ratio as well as the role of metal centers formed on point defects in the kinetics of nucleation have been established, thus paving the way to guided synthesis of single atom catalysts. The predictions are supported by experimental results on sputter deposition of Pt on exfoliated hexagonal boron nitride, as imaged by aberration-corrected scanning transmission electron microscopy.

Atomically precise metal nanoclusters (NCs) represent an emerging sector of light-harvesting antennas by virtue of peculiar atomic stacking fashion, quantum confinement effect, and molecular-like discrete energy band structure. Nevertheless, precise control of charge carriers over metal NCs has yet to be achieved by the short carrier lifetime and intrinsic instability of metal NCs, which renders the complexity of metal NCs-based photosystems with photoredox mechanisms remaining elusive. Herein, fine tuning of charge migration over metal NCs is demonstrated by constructing directional charge transfer channels in multilayered heterostructure enabled by a facile layer-by-layer (LbL) assembly approach, wherein oppositely charged branched poly-ethylenimine (BPEI) and glutathione (GSH)-capped gold NCs [Au x NCs, Au 25 (GSH) 18 NCs] are alternately deposited on the metal oxide (MOs: TiO 2 , WO 3 , Fe 2 O 3 ) substrates. TheAu x (Au 25 ) NCs layer serves as light-harvesting antennas for engendering charge carriers, andBPEI interim layer uniformly intercalated at the interface of Au x NCs layer constitutes the tandem hole transport channel for motivating the charge transfer cascade, resulting in the considerably enhanced photoelectrochemical water oxidation performances. Besides, poor photo-stability of Au x NCs is surmounted by stimulating the hole transfer kinetics process., (© 2023 Wiley-VCH GmbH.)

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]

Recent researches in metal nanoclusters (NCs) have prompted their promising practical applications in biomedical fields as novel inorganic luminophores. More recently, to further improve the photoluminescence (PL) performance of NCs, the aggregation-induced emission (AIE) effect has been introduced to develop highly luminescent metal NCs and metal complex materials. In this review, we start our discussion from recent progresses on AIE materials developments. Then, we address our understandings on the PL properties of thiolated metal NCs. Subsequently, we link thiolated metal NCs with AIE effect. We also highlight some recent advances in synthesizing the AIE-type metal complex nanomaterials. We finally discuss visions and directions for future development of AIE-type metal complex nanomaterials. [ABSTRACT FROM AUTHOR]

Alendronate sodium (ALDS) is an important and regularly used medicine in clinical therapy of osteoporosis. In this work, a new analytical method is developed for the detection of ALDS based on a fluorescent platform of copper(II)–mediated silver nanoclusters (AgNCs). Specifically, Cu 2+ can selectively bind with DNA-stabilized AgNCs and thus greatly quench their red fluorescence. In the presence of ALDS, their fluorescence can largely recover again owing to the stronger coordination of ALDS with Cu 2+ . On the basis of such a mechanism, fluorescence “on-off-on” mode of the nanoprobe is applied to detect ALDS in a wide linear range of 800 pM–200 μM, with a detection limit of 100 pM. Compared with previously reported methods, the present approach has significant advantages regard to simplicity, high sensitivity, and a wide detectable concentration range. This method has been successfully applied in ALDS assay in tablets and human body fluids. [ABSTRACT FROM AUTHOR]

Both the electronic and surface structures of metal nanomaterials play critical roles in determining their chemical properties. However, the non-molecular nature of conventional nanoparticles makes it extremely challenging to understand the molecular mechanism behind many of their unique electronic and surface properties. In this work, we report the synthesis, molecular and electronic structures of an atomically precise nanoparticle, [Ag206L72] q (L = thiolate, halide; q = charge). With a four-shell Ag7@Ag32@Ag77@Ag90Ino-decahedral structure having a nearly perfect D5h symmetry, the metal core of the nanoparticle is co-stabilized by 68 thiolate and 4 halide ligands. Both electrochemistry and plasmonic absorption reveal the metallic nature of the nanoparticles, which is explained by density functional theory calculations. Electronically, the nanoparticle can be considered as a superatom, just short of a major electron shell closing of 138 electrons (q = –4). More importantly, many of ligands capping on the nanoparticle are labile due to their low-coordination modes, leading to high surface reactivity for catalysing the synthesis of indoles from 2-ethynylaniline derivatives. The results exemplify the power of the atomic-precision nanocluster approach to catalysis in probing reaction mechanisms and in revealing the interplay of heterogeneous reactivities, electronic and surface structural dynamics, thereby providing ways for optimization. [ABSTRACT FROM AUTHOR]

Ultrasmall (<2 nm) ligand-protected metal nanoclusters (NCs) have been an emerging class of functional materials with rich coordination chemistry, finding increasing acceptance in both basic and applied research owing to their atomic precision, well-defined molecular structure, and intriguing molecular-like properties. The presence of ligands on metal NCs is crucial not only for maintaining their atomic precision and well-defined structure, but also for their rich coordination chemistry with noble metals, influencing the synthesis, and physicochemical and catalytic properties of metal NCs. In this review, we discuss the important roles of ligands to metal NCs, taking water-soluble gold nanoclusters (Au NCs) as an example. The review covers the fundamental understandings (and advances) on the roles of ligands to water-soluble Au NCs in the synthesis ( e.g., influencing the size and formation rate, and revealing the growth mechanisms), physicochemical properties ( e.g., geometrical structure, chirality, stability, solubility, and electronic, photoluminescence and biological properties) and catalytic applications ( e.g., accessibility, activity, selectivity, and coordination of catalytic mechanism of quasi-homogeneous catalysts and immobilization of heterogeneous catalysts). The review also highlights some challenging issues on how ligands and ligand engineering could expand the scope of metal NCs in the synthesis, physicochemical properties, and catalytic application. [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]

A new type of copper nanoclusters was synthesized by a one-pot reaction using cysteamine as a capping agent and reducing agent (Cys-CuNCs). The synthesized CuNCs exhibited a spherical shape and a monodisperse and strong fluorescent emission characteristic peak at 430 nm when exciting at 330 nm. The Cys-CuNCs were demonstrated as a fluorescent chemodosimeter for the selective detection of Al 3+ . In the presence of Al 3+ , the fluorescent emission of the Cys-CuNCs was considerably enhanced, while other studied metal ions did not show this phenomenon. The fluorescent intensity near 380 nm linearly increased with an increasing Al 3+ concentration. The proposed method provided a working range of 1–7 µM with a low detection limit of 26.7 nM and was applied to determine Al 3+ in drinking water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

The rapid and increasing use of the nanomaterials (NMs), nanostructured materials (NSMs), metal nanoclusters (MNCs) or nanocomposites (NCs) in the development of electrochemiluminescence (ECL) nanobiosensors is a significant area of study for its massive potential in the practical application of nanobiosensor fabrication. Recently, NMs or NSMs (such as AuNPs, AgNPs, Fe3O4, CdS QDs, OMCs, graphene, CNTs and fullerenes) or MNCs (such as Au, Ag, and Pt) or NCs of both metallic and non-metallic origin are being employed for various purposes in the construction of biosensors. In this review, we have selected recently published articles (from 2014-2017) on the current development and prospects of label-free or direct ECL nanobiosensors that incorporate NCs, NMs, NSMs or MNCs. [ABSTRACT FROM AUTHOR]

An immunohistochemical method is described to visualize the distribution of metallothioneins 1/2 (MT 1/2) and metallothionein 3 (MT 3) in human ocular tissue. It is making use of (a) antibodies conjugated to gold nanoclusters (AuNCs) acting as labels, and (b) laser ablation (LA) coupled to inductively coupled plasma -- mass spectrometry (ICP-MS).Water-soluble fluorescent AuNCs (with an average size of 2.7 nm) were synthesized and then conjugated to antibody by carbodiimide coupling. The surface of the modified AuNCs was then blocked with hydroxylamine to avoid nonspecific interactions with biological tissue. Immunoassays for MT 1/2 and MT 3 in ocular tissue sections (5 µm thick) from two post mortem human donors were performed. Imaging studies were then performed by fluorescence using confocal microscopy, and LA-ICP-MSwas performed in the retina to measure the signal for gold. Signal amplification by the >500 gold atoms in each nanocluster allowed the antigens (MT 1/2 and MT 3) to be imaged by LA-ICP-MS using a laser spot size as small as 4 µm. The image patterns found in retina are in good agreement with those obtained by conventional fluorescence immunohistochemistry which was used as an established reference method. [ABSTRACT FROM AUTHOR]

Noble metal nanoclusters have attracted great attentions in the area of fluorescence related applications due to their special properties such as low toxicity, excellent photostability and bio-compatibility. However, they still describe disadvantages for low quantum yield compared to quantum dots and organic dyes though the brightness of the fluorescence play an important role for the efficiency of the applications. Attentions have been attracted for exploring strategies to enhance the fluorescence based on the optical fundamentals through various protocols. Some methods have already been successfully proposed for obtaining relative highly fluorescent nanoclusters, which will potentially describe advantages for the application. In this review, we summarize the approach for enhancement of the fluorescence of the nanoclusters based on the modification of the properties, improvement of the synthesis process and optimization of the environment. The limitation and directions for future development of the fabrication of highly fluorescent metal nanoclusters are demonstrated. [ABSTRACT FROM AUTHOR]

• Dual-signal fluorescent test strips were fabricated using MNCs with AIE properties. • Test strips displayed ratiometric fluorescence changes during the spoilage trial. • Test strips is suitable for in-situ monitoring of seafood freshness by naked eyes. • The test strips successfully described the freshness degree of seafood. With the food safety issues abounding, exploring reliable and efficient methods for evaluating food safety is crucial. Herein, a ratiometric test strip was proposed by using green-yellow fluorescent d -penicillamine capped silver nanocluster (DPA-AgNCs) as indicator and red-emitting bimetallic gold/silver nanoclusters (AuAgNCs) as an internal reference, providing a real-time and visual monitoring system for food freshness. Results showed that the as-prepared DPA-AgNCs displayed an excellent response and good sensitivity for volatile basic nitrogens (VBNs), with a limit of detection (LOD) of 0.51 μM and 0.08 ppm for spermidine and ammonia hydroxide, respectively. Subsequently, a ratiometric test strip was developed to visually monitor ammonia vapour, displaying an obvious fluorescence colour variation from mustard to deep-red. Moreover, the presented ratiometric test strip was successfully applied for non-contact and visual evaluating and monitoring VBNs in the shrimp sample, showing high potential for in-situ monitoring. [ABSTRACT FROM AUTHOR]

[Display omitted] • Au 38− x Ag x NCs is prepared by Ag doping in Au 38 NCs and impregnated on ZIF-8. • The doped Au 38− x Ag x NCs is studied by using single crystal X-ray crystallography. • Au 38− x Ag x NCs@ZIF-8 demonstrates specific capacitance of 378.3 F g−1. Fast-charging storage devices have attained attention in recent years due to their prospective wide range of applications in microelectronic gadgets and hybrid electric vehicles. In the pursuit of new efficient high-capacity electrodes, the implication of atomically precise metal nanoclusters (NCs) in the field of supercapacitors is rare. Herein, structurally distorted atomically precise doped Au 38− x Ag x NCs protected by 2,4-dimethylbenzenethiolate (2,4-DMBT) were synthesized by doping Ag atoms to the parent monometallic Au 38 NCs. A general strategy to integrate structurally distorted atomically precise doped Au 38− x Ag x NCs with ZIF-8 (Au 38− x Ag x NCs@ZIF-8) was employed for methodical electrochemical and physicochemical studies of intrinsic energy storage mechanisms. The structural changes of doped Au 38− x Ag x NCs@ZIF-8 were systematically revealed and the effect of heteroatom doping, synergistic effect, reduced HOMO-LUMO gap (HLG) of highly distorted doped Au 38− x Ag x NCs@ZIF-8 resulted in enhanced electronic transfer kinetics, ultimately improving specific capacitance 2.2 times higher than the parent monometallic Au 38 NCs. Doped Au 38− x Ag x NCs@ZIF-8 based hybrid supercapacitor (HSC) provides a high energy density of 14.75 Wh kg−1 and power density of 2212.8 W kg−1. The development of structurally distorted atomically precise doped Au 38− x Ag x NCs@ZIF-8 electrode material can pave the ways for doped metal nanoclusters for next-generation energy storage devices. [ABSTRACT FROM AUTHOR]

On the basis of temperature dependencies of internal energy the size dependences of heat of fusion and heat of freezing for gold, cuprum, aluminum and cobalt nanoclusters have been calculated. For the simulation the Monte-Carlo method has been used and interaction between atoms has been described by many-body Gupta potential.

Size dependence of the nanocluster melting temperature Tm has been analyzed using some similarity considerations and generalized Thomson’s formula Tm=Tm(∞)(1-α/R) where R is the particle radius, Tm(∞) is the macroscopic melting temperature and α is a parameter having the dimension of length and being the reduction parameter for R. Using Thomson’s formula and extrapolation to Tm=0K, the parameter α was calculated for nanoclusters of several metals with different types of lattice. It has been found that in most cases this parameter is close in magnitude to the first coordination sphere radius.

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 authors describe a two-step strategy for in-situ dispersive solid phase extraction ( is-dSPE) of Cr(VI) ion (chromate) prior to its determination by using copper nanoclusters capped with 4,6-diamino-2-mercaptopyrimidine (DAMP-CuNCs) as a fluorescent probe. By emulating the formation of layered double hydroxides and taking advantage of their compositions, the extraction of chromate is accomplished by rapidly dispersing a suspension of mixed hydroxides of Mg and Al into the sample solution. After enrichment, chromate is directly quantified through selective quenching of the fluorescence of DAMP-CuNCs. This results from an inner filter effect caused by chromate only, while other anions have no effect. Under optimized conditions, the method has a linear response in the 1-7 μM chromate concentration range, and the lower limit of detection is 0.31 μM. The is-dSPE has improved detection sensitivity and has provided a highly selective response. It was successfully applied to the determination of chromate in (spiked) water samples, and the results agreed well with data obtained by ICP-OES. [ABSTRACT FROM AUTHOR]

A sensitive and selective luminescent nanoprobe (referred to as DEPN) is designed for the determination of Cu(II) ions. DEPN shows two emission peaks, one at 602 nm and caused by [Ru(bpy)], the other (peaking at 500 nm) caused by silver nanoclusters (AgNCs). The luminescence of the ruthenium complex is inert and acts as the internal reference signal, while that of the AgNCs is quenched by Cu(II) ions. Under 350 nm photoexcitation, a linear relationship is found between the ratio of emission intensity (I/I) and the concentration of Cu(II) ions in the 0.1-16 μM range. The detection limit of Cu(II) ions is estimated to be 50 nM. The DEPN was applied to the determination of Cu(II) ions in (spiked) water samples, and to intracellular imaging of Cu(II) in HeLa cells using confocal fluorescence microscopy. [ABSTRACT FROM AUTHOR]

Unstabilized, pH-responsive soluble crosslinked polymers (microgels) bearing pendant trialkylamino or pyridyl groups and containing size-controlled Au or Pd nanoclusters have been prepared by radical copolymerization in dilute solution, followed by loading with HAuCl 4 or Pd(OAc) 2 and chemical reduction. The hydrodynamic volume, the solubility and the partition between immiscible solvents of the microgels and of the resulting microgel-metal nanocomposites have been investigated, together with the variation of these parameters with the solution pH: separation of our microgel-containing metal nanoclusters from aqueous solutions can be accomplished by precipitation or by extraction into an organic solvent phase upon pH change, thus enabling their potential recovery. The catalytic performance of the microgels in the aerobic oxidation of benzyl alcohol (Au) and in Sonogashira coupling reactions (Pd) has been determined. The microgel-Au nanocomposites exhibit poor catalytic activity, whereas better results have been obtained in the copper-free Sonogashira reaction with microgel-Pd nanocomposites as precatalysts. [ABSTRACT FROM AUTHOR]

Soy protein isolate (SPI)-based materials are abundant, biocompatible, renewable and biodegradable. In order to improve the tensile strength (TS) of SPI films, we prepared a novel composite film modified with microcrystalline cellulose (MCC) and metal nanoclusters (NCs) in this study. The effects of the modification of MCC on the properties of SPI-Cu NCs and SPI-Zn NCs films were investigated. Attenuated total reflectance-Fourier transformed infrared spectroscopy analyses and X-ray diffraction patterns characterized the strong interactions and reduction of the crystalline structure of the composite films. Scanning electron microscopy (SEM) showed the enhanced cross-linked and entangled structure of modified films. Compared with an untreated SPI film, the tensile strength of the SPI-MCC-Cu and SPI-MCC-Zn films increased from 2.91 to 13.95 and 6.52 MPa, respectively. Moreover, the results also indicated their favorable water resistance with a higher water contact angle. Meanwhile, the composite films exhibited increased initial degradation temperatures, demonstrating their higher thermostability. The results suggested that MCC could effectively improve the performance of SPI-NCs films, which would provide a novel preparation method for environmentally friendly SPI-based films in the applications of packaging materials. [ABSTRACT FROM AUTHOR]

The authors described gold nanoclusters (AuNCs) for use on an 'on − off − on' NIR fluorescent probe for the determination of citrate and Cu(II) ion. The AuNCs were prepared by a microwave-assisted method using BSA as both the stabilizing and reducing agent. The resulting BSA-capped AuNCs display NIR fluorescence peaking at 680 nm under 500 nm excitation, a quantum yield of ~6.0%, an average size of 2.8 ± 0.5 nm, water-dispersibility, stability and biocompatibility. The on−off probe for Cu(II) is based on the interaction between Cu(II) and BSA which causes the fluorescence of the BSA−AuNCs to be quenched. The quenched fluorescence is recovered on addition of vitamin C (VC), obviously due to complexation of Cu(II) by citrate. The probe was employed to image Cu(II) and citrate in HeLa cells and in aqueous solutions. The method works in the 20 nM to 0.1 mM concentration range for Cu(II), and in the 8 nM to 120 μM concentration range for VC. [ABSTRACT FROM AUTHOR]

Herein, we report a convenient approach to purify water-soluble bovine serum albumin (BSA)-capped metal nanoclusters by pH-induced precipitation under acidic conditions. The fluorescence of metal nanoclusters could be completely recovered upon the re-dispersion of nanoparticles into basic media. BSA metal nanoclusters have been prepared to monitor pH at highly acidic medium. When pH decreased, the fluorescence of the nanoclusters under a UV lamp decreased and completely disappeared after pH 4. And a fluorescent pH sensor for pH monitoring has been developed based on the “OFF–ON” signal switch of the gold clusters agarose hydrogel. [ABSTRACT FROM AUTHOR]

Slow desalination kinetics and poor durability constrain the practical application of faradic electrode-directed capacitive deionization (FDI) systems. In view of this, we developed a temperature-mediated in-situ synthesis strategy for fabricating Sb nanoclusters inside carbon nanofibers (Sb NCs@CNF) as Cl− capturing electrodes for high-efficiency FDI. The synthetic strategy allows "temperature-controlled evaporation" of Sb species from the nanofibers, which not only makes the formation of ultrasmall Sb NCs possible but also provides CNF shells to enhance the structural stability and electrical conductivity of Sb NCs. Benefiting from the specific interaction between Sb species and Cl− ions, ultrasmall size, high surface atom ratio of Sb NCs, as well as the protective CNFs shell, the as-fabricated Sb NCs@CNF-based Cl−-driven FDI achieved fast desalination rate (up to 0.24 mg g−1 s−1, through expanding the contribution of surface-controlled capacitance) and excellent cycling stability (only 12.4 % desalination capacity reduction after 30 cycles). In addition to the unprecedented design of Sb NCs-based Cl− capturing electrode materials, this study also provides a paradigm in the temperature-mediated in-situ synthesis of non-coinage MNCs, which may stimulate more research activities in the design and application of carbon-protected MNCs. Ultra-small Sb nanoclusters are unprecedentedly fabricated and employed as chloride-capturing faradic electrodes for fast capacitive deionization. [Display omitted] • Sb nanoclusters (Sb NCs) is unprecedentedly employed as Cl−-capturing electrodes for capacitive desalination (CDI). • The study provides an alternative synthesis strategy and promotes the application of non-coinage metal NCs. • The Sb NCs could accelerate the desalination process of faradic CDI by enhancing the surface-controlled contribution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi nanoclusters were synthesized inside electrospun carbon nanofiber (Bi NCs@CNF). • Bi NCs@CNF was first introduced to capacitive deionization (CDI) for Cl- removal. • A unique flow-through cell was employed to accelerate the ion mass transfer. • The desalination rate of our system outperforms most existing CDI systems. Faradic electrode-directed capacitive deionization (faradic-based CDI) as a green and eco-friendly technique is particularly promising in addressing the freshwater crisis, but its practical applications are plagued by the sluggish desalination kinetic. After deciphering its dynamic desalination process, two rate-determine steps (RDS) are identified, i.e. , the ion diffusion inside the faradic electrode (RDS #1) and mass transfer process in the electrolyte (RDS #2). Therefore, we propose a synergetic strategy to upshift the desalination rate limit of faradic-based CDI through the integration of delicate material design with rational cell architecture. Specifically, deploying ultrasmall Bi nanoclusters impregnated carbon nanofibers (Bi NCs@CNF) as chloride-capturing electrodes and constructing a flow-through CDI (FT-CDI) system to accelerate the diffusion process (RDS #1) and shorten the mass transfer pathway (RDS #2), respectively. As expected, Bi NCs@CNF-based FT-CDI performs super-fast desalinization (0.56 mg g−1 s−1) and excellent cyclic stability. Taken together, our study opens an avenue in upshifting the desalination kinetics of faradic-based CDI based on the joint power of both "material design" and "cell architecture", which may motivate the development of highly-efficient desalination systems. [ABSTRACT FROM AUTHOR]

In the present work, a methotrexate (MTX) optical nanosensor involving the generation of a double pH gradient in which silver nanoclusters (AgNCs) act as an optical probe is presented. The proposed strategy is based on the pH-dependent agglomeration and dispersion behavior of the AgNCs and the consequent reversible changes in the spectroscopic signal. MTX is an antineoplastic drug used in high doses (HD) for the treatment of different types of cancer. Interestingly, the presence of the AgNCs enhances the signal of MTX, a phenomenon that was exploited to generate a simple, fast, and sensitive method for MTX quantitation in the presence of uncalibrated components based on second-order data generation and chemometric data modeling. The successful calibration models were obtained by unfolded partial least squares coupled to residual bilinearization, which was able to deal with data with high spectral collinearity while achieving the second-order advantage. The proposed sensing strategy reached limits of detection and quantitation of 3.3 nmol L–1 and 10.1 nmol L–1, respectively. These results support the applicability of the method for the detection and quantitation of MTX at clinically relevant concentrations, considering that plasma levels after the HD-MTX treatment should reach concentrations of 0.1 µmol L–1 at 72 h to minimize side effects. Furthermore, the generation of second-order data and chemometric data modeling allowed the accurate prediction of MTX in the presence of uncalibrated compounds. The developed sensing platform is presented as an alternative of great interest, which allows the simple, fast, sensitive, and selective quantitation of MTX. • Development of a MTX nanosensor based on AgNCs in a double pH gradient. • Application of the pH-switchable agglomeration and dispersion behavior of AgNCs. • Quantitation of MTX in the presence of interferences by multiway calibration. • Assessment of method suitability for MTX quantitation at clinically relevant concentrations. • Generation of a simple, fast, sensitive, and selective sensing platform for MTX quantitation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Comprehensive overview of main synthesis strategies of metal nanoclusters (MNCs). • Summary of optical, electrical and catalytic properties of MNCs in sensing fields. • Illustration of the sensing mechanisms of MNC-based sensors for food contaminants. • Pointing out the challenges and development tendency of MNCs-based sensors. Frequent food safety problems have brought great threat to people's life and health in recent years. Therefore, it is of urgent demand to exploit efficient sensing methods for detecting contaminants in food matrix. Effective food safety monitoring technology can be developed by integrating food detection with functional nanomaterials. Nowadays, metal nanoclusters (MNCs) are regarded as very promising nanomaterials on account of their significantly superior properties over metal nanoparticles. The excellent optical property, electrical performance and catalytic ability broaden the application prospect of MNCs for developing new sensors. This review comprehensively introduces the main synthesis strategies of MNCs, and summarizes the applications of them to construct sensitive and specific sensing strategies for analyzing various contaminants in food substrates in the past ten years. Furthermore, the potential applications of fluorescence, electrochemistry (including electrochemical catalysis and electrochemiluminescence), and mimic enzyme properties of MNCs in food safety monitoring were discussed in detail, and their sensing mechanisms were elaborately clarified through typical sensing application examples. The review is concluded with the perspective on the application challenges and development tendency of MNCs-based sensors. We hope valuable ideas will be provided in this review for designing MNCs-based sensors according to their unique properties in sensing fields. [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.

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.

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., (© 2022 John Wiley & Sons Ltd.)

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 CO 2 reduction reaction (CO 2 RR).

Abstract: Coating formation over the surface of a highly porous material on the basis of activated carbon fiber is considered. The coating is applied from a colloidal solution of metals, with the goal of producing electrodes and composite polymer structures. Experiments show that porous carbon materials may be metallized by means of metal nanoclusters (measuring 2-10 nm) on the basis of electrophoresis, without loss of the initial porosity. [ABSTRACT FROM AUTHOR]