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The structural transformation of high-nuclearity silver clusters from one to another induced by specific stimuli is of scientific significance in terms of both cluster synthesis and reactivity. Herein, we report two silver-thiolate clusters, [Mo 6 O 22 @Ag 44 ] and [Mo 8 O 28 @Ag 50 ], which are templated by isopolymolybdates inside and covered by i PrS − and PhCOO − ligands on the surfaces. Amazingly, the [Mo 8 O 28 @Ag 50 ] can be transformed from [Mo 6 O 22 @Ag 44 ] by adding PhCOOH which increases the degree of condensation of molybdates template from Mo 6 O 22 8- to Mo 8 O 28 8- , then enlarging the outer silver shell from Ag 44 to Ag 50 . The evolution of solution species revealed by time-dependent electrospray ionization mass spectrometry (ESI-MS) suggests a breakage-growth-reassembly (BGR) transformation mechanism. These results not only provide a combined assembly strategy (anion-template + induced transformation) for the synthesis of silver-thiolate clusters but also help us to better understand the complex transformation process underpinning the assembly system. Understanding how one metal nanocluster transforms into another is of synthetic and fundamental importance. Here, the authors use mass spectrometry to reveal an acid-induced structural transformation between two Ag clusters that proceeds via a breakage-growth-reassembly mechanism.

High-nuclearity silver clusters are appealing synthetic targets for their remarkable structures, but most are isolated serendipitously. We report here six giant silver-thiolate clusters mediated by solvents, which not only dictate the formation of an octahedral Ag 6 4+ kernel, but also influence the in situ-generated Mo-based anion templates. The typical sevenfold symmetric silver nanowheels show a hierarchical cluster-in-cluster structure that comprises an outermost Ag 56 shell and an inner Ag 6 4+ kernel in the centre with seven MoO 4 2− anion templates around it. Electrospray ionization mass spectrometry analyses reveal the underlying rule for the formation of such unique silver nanowheels. This work establishes a solvent–intervention approach to construct high-nuclearity silver clusters in which both the formation of octahedral Ag 6 4+ kernel and in situ generation of various Mo-based anion templates can be simultaneously controlled. High-nuclearity silver clusters are appealing synthetic targets for their remarkable structures, but most are isolated serendipitously. Here, the authors describe the rational use of solvents to form cluster-in-cluster silver nanowheels, which comprise an octahedral Ag 6 4+ core surrounded by a Ag 56 cage of unusual seven-fold symmetry.

Thiacalix[4]arenes as a family of promising ligands have been widely used to construct polynuclear metal clusters, but scarcely employed in silver nanoclusters. Herein, an anion-templated Ag 88 nanocluster (SD/Ag88a) built from p -tert-butylthiacalix[4]arene (H 4 TC4A) is reported. Single-crystal X-ray diffraction reveals that C 4 -symmetric SD/Ag88a resembles a metal-organic super calix comprised of eight TC4A 4− as walls and 88 silver atoms as base, which can be deconstructed to eight [CrO 4 @Ag 11 (TC4A)(EtS) 4 (OAc)] secondary building units arranged in an annulus encircling a CrO 4 2− in the center. Local and global anion template effects from chromates are individually manifested in SD/Ag88a. The solution stability and hierarchical assembly mechanism of SD/Ag88a are studied by using electrospray mass spectrometry. The Ag 88 nanocluster represents the highest nuclearity metal cluster capped by TC4A 4− . This work not only exemplify the specific macrocyclic effects of TC4A 4− in the construction of silver nanocluster but also realize the shape heredity of TC4A 4− to overall silver super calix. The assembly of giant silver clusters by using macrocylic multidentate ligand remains a challenge. Here, the authors synthesize a chromate-templated 88-nuclei silver super calix and reveal the role of anion templating effects and a hierarchical assembly mechanism.

Nanoarmor strengthens the structure and function of single cells by coating and encapsulating nanomaterials on single cells. It has tremendous potential for environmental, energy, and medical applications.Nanoarmor can isolate cells from their environment, endowing them with catalytic functions and photoelectric properties, and protecting the patient when used for medical applications.Nanoarmor can endow cells with self-driving capability, which has good prospects for applications in disease treatments.Nanoarmor can form heterojunctions on cells to facilitate electron transfer.Nanoarmor can be formed through biomineralization or biomimetic mineralization, with different involvements of the cell. Single cell modification or hybridization technology has become a popular direction in bioengineering in recent years, with applications in clean energy, environmental stewardship, and sustainable human development. Here, we draw attention to nanoarmor, a representative achievement of cytoprotection and functionalization technology. The fundamental principles of nanoarmor need to be studied with input from multiple disciplines, including biology, chemistry, and material science. In this review, we explain the role of nanoarmor and review progress in its applications. We also discuss three main challenges associated with its development: self-driving ability, heterojunction characteristics, and mineralization formation. Finally, we propose a preliminary classification system for nanoarmor. Single cell modification or hybridization technology has become a popular direction in bioengineering in recent years, with applications in clean energy, environmental stewardship, and sustainable human development. Here, we draw attention to nanoarmor, a representative achievement of cytoprotection and functionalization technology. The fundamental principles of nanoarmor need to be studied with input from multiple disciplines, including biology, chemistry, and material science. In this review, we explain the role of nanoarmor and review progress in its applications. We also discuss three main challenges associated with its development: self-driving ability, heterojunction characteristics, and mineralization formation. Finally, we propose a preliminary classification system for nanoarmor.

The exploration of artificial metal-peptide assemblies (MPAs) is one of the most exciting fields because of their great potential for simulating the dynamics and functionality of natural proteins. However, unfavorable enthalpy changes make forming discrete complexes with large and adaptable cavities from flexible peptide ligands challenging. Here, we present a strategy integrating metal-cluster building blocks and peptides to create chiral metal-peptide assemblies and get a family of enantiopure [ R-/S- Ni 3 L 2 ] n (n = 2, 3, 6) MPAs, including the R-/S- Ni 6 L 4 capsule, the S- Ni 9 L 6 trigonal prism, and the R-/S- Ni 18 L 12 octahedron cage. X-ray crystallography shows MPA formation reactions are highly solvent-condition-dependent, resulting in significant changes in ligand conformation and discrete cavity sizes. Moreover, we demonstrate that a structure transformation from Ni 18 L 12 to Ni 9 L 6 in the presence of benzopyrone molecules depends on the peptide conformational selection in crystallization. This work reveals that a metal-cluster building block approach enables facile bottom-up construction of artificial metal-peptide assemblies. The use of metal clusters to construct artificial protein-mimic structures with adaptable cavities has potential for simulating the dynamics and functionality of natural proteins. Here, the authors develop a family of chiral metal-peptide assemblies using {Ni3} clusters and flexible peptides, resulting in structures such as octahedral cages, trigonal prisms, and capsules.

Hydrogen-bonded assembly of multiple components into well-defined icosahedral capsules akin to virus capsids has been elusive. In parallel, constructing robust zeolitic-like cluster-based supramolecular frameworks (CSFs) without any coordination covalent bonding linkages remains challenging. Herein, we report a cluster-based pseudoicosahedral H-bonded capsule Cu 60 , which is buckled by the self-organization of judiciously designed constituent copper clusters and anions. The spontaneous formation of the icosahedron in the solid state takes advantage of 48 charge-assisted CH···F hydrogen bonds between cationic clusters and anions (PF 6 - ), and is highly sensitive to the surface protective ligands on the clusters with minor structural modification inhibiting its formation. Most excitingly, an extended three-periodic robust zeolitic-like CSF, is constructed by edge-sharing the resultant icosahedrons. The perpendicular channels of the CSF feature unusual 3D orthogonal double-helical patterns. The CSF material not only keeps its single-crystal character in the desolvated phase, but also exhibits excellent chemical and thermal stabilities as well as long-lived phosphorescence emission. H-bonded assembly of multiple components into well-defined icosahedral capsules has been elusive, and constructing stable sophisticated cluster-based supramolecular frameworks without coordinative bonding linkages remains challenging. Here, the authors report a cluster-based icosahedral H-bonded capsule Cu 60 and its self-propagation into a 3D robust zeolitic-like supramolecular framework.

Innovation in synthesis methodologies is crucial for advancing the discovery of new materials. This work reports the electrosynthesis of a [Au13(4‐tBuPhC≡C)2(Dppe)5]Cl3 nanocluster (Au13 NC) protected by alkynyl and phosphine ligands. From simple precursor, HAuCl4 and ligands, the whole synthesis is driven by a constant potential in single electrolytic cell. X‐ray crystallography determines its total structure. Control experiments, cyclic voltammetry, Proton Nuclear Magnetic Resonance (1H NMR), gas chromatography, and other characterizations demonstrate that a critical tetranuclear Au(I) complex defines the electrochemical redox behavior of the reaction solution. The critical role of a base (e.g., triethylamine) is to suppress the hydrogen evolution reaction at the cathode, paving the way for the reduction of Au ions. To resolve the problem of over‐reduction and deposition of Au on the cathode, pulsed electrolysis, which is specific to electrosynthesis is employed. It significantly improves the reaction rate and the isolated yield of Au13. To extend the application scope, another four NCs protected by different ligands, [Au13(4‐FPhC≡C)2(Dppe)5]Cl3, [Au8(2‐CF3PhC≡C)2(Dppp)4](PF6)2, [Au11(Dppp)5]Cl3, and [Au8(SC2H4Ph)2(Dppp)4]Cl2 are synthesized electrochemically, demonstrating the versatility of the strategy. In this work, atomically precise Au nanoclusters are fabricated by electrochemical method. The synthesis mechanism is explored. Simply by adjusting the potential waveform, the yield of Au nanoclusters is significantly enhanced, highlighting its technical superiority. To expand the application scope, another four Au nanoclusters are produced by replacing certain ingredients, demonstrating the versatility of the strategy.

Buckminsterfullerene (C60) represents a perfect combination of geometry and molecular structural chemistry. It has inspired many creative ideas for building fullerene-like nanopolyhedra. These include other fullerenes, virus capsids, polyhedra based on DNA, and synthetic polynuclear metal clusters and cages. Indeed, the regular organization of large numbers of metal atoms into one highly complex structure remains one of the foremost challenges in supramolecular chemistry. Here we describe the design, synthesis, and characterization of a Ag180 nanocage with 180 Ag atoms as 4-valent vertices (V), 360 edges (E), and 182 faces (F)––sixty 3-gons, ninety 4-gons, twelve 5-gons, and twenty 6-gons––in agreement with Euler’s rule V − E + F = 2. If each 3-gon (or silver Trigon) were replaced with a carbon atom linked by edges along the 4-gons, the result would be like C60, topologically a truncated icosahedron, an Archimedean solid with icosahedral (I h) point-group symmetry. If C60 can be described mathematically as a curling up of a 6.6.6 Platonic tiling, the Ag180 cage can be described as a curling up of a 3.4.6.4 Archimedean tiling. High-resolution electrospray ionization mass spectrometry reveals that {Ag₃}n subunits coexist with the Ag180 species in the assembly system before the final crystallization of Ag180, suggesting that the silver Trigon is the smallest building block in assembly of the final cage. Thus, we assign the underlying growth mechanism of Ag180 to the Silver-Trigon Assembly Road (STAR), an assembly path that might be further employed to fabricate larger, elegant silver cages.

Desorption electrospray ionization mass spectrometry (DESI-MS) has been used for monitoring solid-state organic reaction in ambient air, specifically the Baeyer-Villiger (BV) type reaction involving the oxidation of ketones (benzophenone or deoxybenzoin) by m-chloroperbenzoic acid (m-CPBA) in solid-state. The DESI mass spectra obtained at regular intervals during the BV reaction processes are featured, with the amount of ester products increasing as those of ketone reactants decrease. Quantitative analyses of relative intensities of the product, made to quantify the reaction degree of typical solid-state organic reaction (SSOR), show a precision with RSDs of around 5% to 12%, though the RSDs for direct analysis of intensities of the reactant or the product in the solid-state are obviously larger. The kinetics of the Baeyer-Villiger type reactions in solid-state are shown to be dramatically different, in reaction rate, kinetic curve, as well as concentration dependence, from those of the same reactions taking place in solution. DESI-MS has been used for monitoring the kinetics of the Baeyer-Villiger reaction about oxidation of ketone (benzophenone or deoxybenzoin) by m-chloroperbenzoic cid in solid sate.

Soil heavy metals pollution can cause many serious environment problems because of involving a very complex pollution process for soil health. Therefore, it is very important to explore methods that can effectively evaluate heavy metal pollution. Researchers were actively looking for new ideas and new methods for evaluating and predicting levels of soil heavy metal pollution. The study on microbial communities is one of the effective methods using gene chip technology. Gene chip technology, as a high-throughput metagenomics analysis technique, has been widely used for studying the structure and function of complex microbial communities in different polluted environments from different pollutants, including the soil polluted by heavy metals. However, there is still a lack of a systematic summarization for the polluted soil by heavy metals. This paper systematically analyzed soil heavy metals pollution via reviewing previous studies on applying gene chip technology, including single species, tolerance mechanisms, enrichment mechanisms, anticipation and evaluation of soil remediation, and multi-directional analysis. The latest gene chip technologies and corresponding application cases for discovering critical species and functional genes via analyzing microbial communities and evaluating heavy metal pollution of soil were also introduced in this paper. This article can provide scientific guidance for researchers actively investigating the soil polluted by heavy metals.