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As a new type of artificial enzyme, a nanozyme is an ideal substitute for natural enzymes and has been successfully applied in many fields. However, in the application of biomolecular detection, most nanozymes have the disadvantages of long reaction times or high detection limits, prompting researchers to search for new efficient nanozymes. In this work, the enzyme-like activities of three polyoxometalate-based iron-organic complexes ([Fe(bpp)2](Mo6O19), [Fe(bpp)2]2(Mo8O26)·2CH3OH, and [Fe(bpp)2]4H[Na(Mo8O26)]3), namely, FeMo6, Fe2Mo8, and Fe4Mo8Na, were analyzed. All three polyoxometalate-based iron-organic complexes were found to be capable of catalyzing hydrogen peroxide (H2O2) to oxidize 3,3′,5,5′-tetramethylbenzidine and o-phenylenediamine, resulting in visible color changes, further exhibiting peroxidase-like activity. Results showed that Fe4Mo8Na had more active sites due to its long chain structure, endowing more prominent peroxidase-like activity compared with Fe2Mo8 and FeMo6. A colorimetric sensing platform for H2O2 and ascorbic acid detection based on Fe4Mo8Na was established. The linear response range for H2O2 detection was 0.5–100 μM, and the detection limit was 0.143 μM. The linear response for ascorbic acid detection ranges from 0 to 750 μM with a detection limit of 1.07 μM. This study provides a new perspective for developing new nanozymes and expanding the sensing and detection application of nanozymes. [ABSTRACT FROM AUTHOR]

A series of unprecedented supramolecular complexes of covalently modified Anderson‐type polyoxometalates (POMs) and α‐cyclodextrins (α‐CDs) have been obtained and characterized in solid state by single‐crystal X‐ray diffraction, and in aqueous solution using various techniques including 1H DOSY NMR, 2D NOESY 1H NMR, isothermal titration calorimetry (ITC), and electrospray ionization time‐of‐flight mass spectroscopy (ESI‐TOF‐MS). It has been demonstrated that the supramolecular assembly process could be modulated by different covalent modification modes of the Anderson POMs, giving rise to a new type of POM/α‐CD complexes featuring organic‐inorganic pseudo‐rotaxane structures, which are in good contrast to those of POM/γ‐CD complexes of poly‐rotaxane structures. Moreover, it is delighted to find that these pseudo‐rotaxanes of POM/α‐CD complexes exhibit stable chirality in aqueous solution, which has not been accomplished in previously reported POM/CD assemblies. [ABSTRACT FROM AUTHOR]

The development and exploration of efficient bifunctional electrocatalysts for water splitting are in high demand and have garnered significant attention in recent years. Herein, by incorporating the advantages of catalytically active polyoxometalates (POMs) and structural stable metal–organic frameworks (MOFs), two POM@MOFs composite materials, Ni4Mo12@Fe and Co4Mo12@Fe, have been successfully prepared via the encapsulation of POMs anions, [MoV12O30(μ2‐OH)10H2{NiII4(H2O)12}]∙14H2O (noted as Ni4Mo12) and [MoV12O30(μ2‐OH)10 H2{CoII(H2O)3}4]∙12H2O (noted as Co4Mo12), into the cavities of MOFs NH2‐MIL‐101(Fe), respectively. Compared to each individual components, Ni4Mo12@Fe and Co4Mo12@Fe composites, as heterogeneous electrocatalysts, both showed enhanced electrocatalytic capacities for efficient oxygen evolution reaction (OER) under alkaline conditions with overpotentials of 332.64 mV for Ni4Mo12@Fe and 352.64 mV for Co4Mo12@Fe at 10 mA cm−2. Additionally, the enhanced electrocatalytic capacities of these two composites could also achieve towards hydrogen evolution reaction (HER). Such a POMs‐assisted strategy for the formation of POM@MOFs composites, described here, paves a new avenue for the development of highly economical, active nonnoble metal bifunctional electrocatalysts for OER and HER. [ABSTRACT FROM AUTHOR]

A d10-Cd cluster containing sandwich-type arsenotungstate [C3H12N2]6[Cd4Cl2(B-α-AsW9O34)2] was synthesized and its structure characterized through elemental analyses, X-ray powder diffraction (XRPD), IR spectroscopy, X-ray photoelectron spectroscopy (XPS), and single-crystal X-ray diffraction. The X-ray analysis revealed that the molecular unit of the compound consists of a captivating tetra-Cd-substituted sandwich-type polyoxoanion, accompanied by six elegantly protonated 1,2-diaminopropane as counter ions. The further novelty of the tetranuclear cadmium cluster lies in its occupied chlorine atom sites. This makes it highly susceptible to coordinate reactions with nitrogen on polycyclic aromatic hydrocarbons, thereby exhibiting different fluorescent signals that facilitate the identification and detection of these carcinogenic substances in methanol. [ABSTRACT FROM AUTHOR]

Nonlinear dynamical systems useful for reservoir computing enhance the physical implementation of computing systems. In this paper we show that electrochemical reactions and their versatility show great potential as reservoirs. The essence of signal processing in such systems is the different levels of ionic current passing through the solution and the detected electrochemical current based on a multidirectional data acquisition system. A basic electrochemical system is also tested to verify the distinction between Faradic and non-Faradic current. Faradic current exhibits a nonlinear effect on the applied voltage and increase the high-dimensional memory capacity. [ABSTRACT FROM AUTHOR]

α‐Keggin polyoxometalates (POMs) [XW12O40]n− (X = Al, Si, P, S) are widely used in batteries owing to their remarkable redox activity. However, the mechanism underlying the applications appears inconsistent with the widely accepted covalent bonding nature. Here, first‐principles calculations show that XW12 are core–shell structures composed of a shell and an XO4n− core, both are stabilized by covalent interactions. Interestingly, owing to the presence of a substantial number of electrons in W12O36 shell, the frontier molecular orbitals of XW12 are not only strongly delocalized but also exhibit superatomic properties with high‐angular momentum electrons that do not conform to the Jellium model. Detailed analysis indicates that energetically high lying filled molecular orbitals (MOs) have reached unusually high‐angular momentum characterized by quantum number K or higher, allowing for the accommodation of numerous electrons. This attribute confers strong electron acceptor ability and redox activity to XW12. Moreover, electrons added to XW12 still occupy the K orbitals and will not cause rearrangement of the MOs, thereby maintaining the stability of these structures. Our findings highlight the structure–activity relationship and provide a direction for tailor‐made POMs with specific properties at atomic level. [ABSTRACT FROM AUTHOR]

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Polyoxometalates (POMs) are ideal components for reversible multi‐electron storage in energy technologies. To‐date, most redox‐applications employ only single, individual POM species, which limits the number of electrons that can be stored within a given potential window. Here, we report that spontaneous redox self‐equilibration during cluster synthesis leads to the formation of two structurally related polyoxovanadates which subsequently aggregate into co‐crystals. This results in systems with significantly increased redox reactivity. The mixed POM system was formed by non‐aqueous self‐assembly of a vanadate precursor in the presence of Mg2+, resulting in two mixed‐valent (VIV/V) species, [(MgOH)V13O33Cl]4− (={MgV13}) and the di‐vanadium‐functionalized species [V14O34Cl]4− (={V14}), which co‐crystallize in a 1 : 1 molar stoichiometry. Experimental data indicate that in the native state, {MgV13} is reduced by three electrons, and {V14} is reduced by five electrons. Electrochemical studies in solution show, that the system can reversibly undergo up to fourteen redox transitions (tentatively assigned to twelve 1‐electron processes and two 2‐electron processes) in the potential range between −2.15 V to +1.35 V (vs Fc+/Fc). The study demonstrates how highly redox‐active, well‐defined molecular mixtures of mixed‐valent molecular metal oxides can be accessed by redox‐equilibration during synthesis, opening new avenues for molecular energy storage. [ABSTRACT FROM AUTHOR]

Fe and Mo co-doped Ni 3 S 2 nanorod array is in situ built on Ni foam using Keplerate polyoxomolybdate as precursor and performs efficiently for electrocatalytic overall water splitting, capable of achieving a low cell voltage of 1.60 V and Faradaic efficiency of nearly 100%. [Display omitted] • Free-standing Fe and Mo co-doped Ni 3 S 2 nanorod array is in situ built on Ni foam using Keplerate polyoxomolybdate as precursor. • Fe-MoS 2 /Ni 3 S 2 @NF is reported first time for overall water splitting. • Fe and Mo co-doping modulates the electronic structure of Ni 3 S 2 and induces abundant active sites. • Fe-MoS 2 /Ni 3 S 2 @NF attains a more exceptional electrochemistry improvement, faster electron transfer, better reaction kinetics and long-term durability. Heazlewoodite nickel sulfide (Ni 3 S 2) is advocated as a promising nonnoble catalyst for electrochemical water splitting because of its unique structure configuration and high conductivity. However, the low active sites and strong sulfur–hydrogen bonds (S–H ads) formed on Ni 3 S 2 surface greatly inhibit the desorption of H ads and reduce the hydrogen and oxygen evolution reaction (HER and OER) activity. Doping is a valid strategy to stimulate the intrinsic catalytic activity of pristine Ni 3 S 2 via modifying the active site. Herein, the Ni foam supported Fe and Mo co-doped Ni 3 S 2 electrocatalysts (Fe-MoS 2 /Ni 3 S 2 @NF) have been constructed using Keplerate polyoxomolybdate {Mo 72 F 30 } as precursor through a facile hydrothermal process. Experimental results certificate that Fe and Mo co-doping can effectively tune the local electronic structure, facilitate the interfacial electron transfer, and improve the intrinsic activity. Consequently, the Fe-MoS 2 /Ni 3 S 2 @NF display more excellent HER and OER activity than MoS 2 /Ni 3 S 2 @NF and bare Ni 3 S 2 @NF by delivering the 10 and 50 mA cm−2 current densities at ultra-low overpotentials of 74/175 and 80/160 mV for HER and OER. Moreover, when coupled in an alkaline electrolyzer, Fe-MoS 2 /Ni 3 S 2 @NF approached the current of 10 mA cm−2 under a cell voltage of 1.60 V and exhibit excellent stability. The strategy to realize tunable catalytic behaviors via foreign metal doping provides a new avenue to optimize the water splitting catalysts. [ABSTRACT FROM AUTHOR]

Polyoxometalates (POMs) are nanosized molecular metal oxide anion clusters with tuneable structures and functionalities, and they exhibit a redox chemistry and catalytic activity in multielectron redox processes. These are typically poor electrical conductors (<10−10 Scm−1), which is attributed to negligible electronic interactions among anions in the solid state. Since the reduced electrons on the d0 metals in POMs are delocalized, electrical conductivity was improved when judicious pathways for the electrons were created by bridging the POMs. Utilized with the electronic interactions between bridging oxygen atoms with the highest occupied molecular orbital in the POMs and the metal dz2 orbitals in the multinuclear platinum complexes, and three mixed‐valent assemblies were synthesized and characterized. Simply mixing Keggin‐type or Dawson‐type POMs with tetranuclear or trinuclear platinum complexes in solution afforded three single crystals, and all three compounds were paramagnetic with mixed oxidation states and better conductivities at room temperature than the parent compounds. [ABSTRACT FROM AUTHOR]

Vanadium-containing heteropoly compounds (HPCs), both in homogeneous and heterogeneous forms, represent a very promising class of materials with adjustable acid and oxidative properties. Herein, a catalytically active HPCs of H3+xPMo12–xVxO40 (x = 1–4) gross-composition were prepared by an environmentally friendly H2O2-affected approach and heterogenized in the form of insoluble salts with Cs+ counterion to obtain stable oxidation catalysts. Structural and textural characteristics of prepared compounds with Cs2.5+xH0.5PMo12–xVxO40 (x = 1–4) gross-composition were investigated by XRD, TGA, IR-ATR, ICP-AES, and N2 adsorption-desorption techniques, and their catalytic properties were tested in the oxidation of 5-hydroxymethylfurfural (5-HMF), a valuable biomass-derived platform chemical. The obtained materials were established to demonstrate retention of the initial Keggin structure during precipitation, low solubility in water, and high structural stability upon fourfold treatment with H2O for 3 h, as well as thermal stability up to 400°C. It was shown that a simple method of replacing H+ ions with large Cs+ cations allows a traditional homogeneous catalyst to function heterogeneously, which simplifies the process of its separation and recycling. The catalytic performance was shown to decrease gradually with reducing x value. The attained Cs5.5H0.5PMo9V3O40 and Cs6.5H0.5PMo8V4O40 solids revealed high activity in 5-HMF transformation to 2,5-diformylfuran with a yield of up to 93%, which opens up prospects for their application in various important fields of synthetic chemistry as heterogeneous oxidation catalysts. [ABSTRACT FROM AUTHOR]

Heteropolyanions (HPAs) are known as the candidate for an anode redox mediator for redox flow polymer electrolyte fuel cells (PEFCs). The electrochemical properties of HPAs differ depending on the transition elements and heteroatoms in HPAs. For example, heteropolytungstate anions (W−HPAs), in which the transition element is tungsten, have a lower one‐electron reduction potential than other HPAs. Therefore, it has been reported that redox flow PEFCs adapted with W−HPAs exhibit high power generation performance. On the other hand, studies on the heteroatoms of HPAs are limited only to electrochemical properties, and statistical and comprehensive studies on the power generation performance of redox flow PEFCs are lacking. Thus, it is beneficial to clarify the optimal heteroatom in order to design anolytes suitable for redox flow PEFCs. In this study, heteropolytungstate anions with different heteroatoms were adapted as anodic redox mediators in a redox flow PEFC. In power generation tests, the redox flow PEFC with an anolyte of zinctungstate anion showed the highest performance. Zinctungstate anion exhibited the fastest reduction and oxidation rates among the W−HPAs investigated in this study. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts with precise structure and extremely high catalytic efficiency remain a fervent focus in the fields of materials chemistry and catalytic science. Herein, a nickel‐substituted polyoxometalate (POM) {NiSb6O4(H2O)3[β‐Ni(hmta)SbW8O31]3}15− (NiPOM) with one extremely exposed nickel site [NiO3(H2O)3] was synthesized using the conventional aqueous method. The uniform dispersion of single nickel center with well‐defined structure was facilely achieved by anchoring nanosized NiPOM on graphene oxide (GO). The resulting NiPOM/GO can couple with CdS photoabsorber for the construction of low‐cost and ultra‐efficient hydrogen evolution system. The H2 yield can reach to 2753.27 mmol gPOM−1 h−1, which represents a record value among all the POM‐based photocatalytic systems. Remarkablely, an extremely high hydrogen yield of 3647.28 mmol gPOM−1 h−1 was achieved with simultaneous photooxidation of commercial waste plastic, representing the first POM‐based photocatalytic system for H2 evolution and waste plastic conversion. This work highlights a straightforward strategy for constructing extremely exposed single‐metal site with precise microenvironment by facilely manipulating nanosized molecular cluster to control individual atom. [ABSTRACT FROM AUTHOR]

A reduced polyoxometalate (POM) functionalized with bisphosphonate (BP) ligands possessing antitumoral properties was used to synthesize metallic gold nanostars (AuNSs) with high reproducibility through a silver-assisted seed growth method. Notably, this study is the first to employ a reduced polyoxometalate as a dual-function reducing and capping agent in the synthesis of gold nanostars. The resulting AuNS@POM composites, characterized by a plasmon band located at 744 nm, combine in a single hybrid nanocomposite alendronate ligands, Mo-(VI) ions, and Au0 centers. The colloidal stability of AuNS@POM was demonstrated in a biological culture medium, and cell experiments were performed to study its antitumoral activity on U87 and MCF7 cell lines from glioblastoma and liver cancer, respectively. First, it was established that the antitumoral activity of the BP POM is enhanced due to the Mo-(V) to Mo-(VI) oxidation process that occurs during AuNS formation. Second, it has been shown that in the presence of the composite, cellular metabolic activity decreases drastically under the effect of irradiation at 808 nm, even leading to almost complete cell death. AuNS@POM therefore exhibits strong antitumor chemo–photothermal activity, paving the way for the development of a type of dual therapeutic agent operating under near-infrared irradiation. [ABSTRACT FROM AUTHOR]

Background: Increased cancer stem cell (CSC) content and SOX2 overexpression are common features in the development of resistance to therapy in hormone-dependent breast cancer, which remains an important clinical challenge. SOX2 has potential as biomarker of resistance to treatment and as therapeutic target, but targeting transcription factors is also challenging. Here, we examine the potential inhibitory effect of different polyoxometalate (POM) derivatives on SOX2 transcription factor in tamoxifen-resistant breast cancer cells. Methods: Various POM derivatives were synthesised and characterised by infrared spectra, powder X-ray diffraction pattern and nuclear magnetic resonance spectroscopy. Estrogen receptor (ER) positive breast cancer cells, and their counterparts, which have developed resistance to the hormone therapy tamoxifen, were treated with POMs and their consequences assessed by gel retardation and chromatin immunoprecipitation to determine SOX2 binding to DNA. Effects on proliferation, migration, invasion and tumorigenicity were monitored and quantified using microscopy, clone formation, transwell, wound healing assays, flow cytometry and in vivo chick chorioallantoic membrane (CAM) models. Generation of lentiviral stable gene silencing and gene knock-out using CRISPR-Cas9 genome editing were applied to validate the inhibitory effects of the selected POM. Cancer stem cell subpopulations were quantified by mammosphere formation assays, ALDEFLUOR activity and CD44/CD24 stainings. Flow cytometry and western blotting were used to measure reactive oxygen species (ROS) and apoptosis. Results: POMs blocked in vitro binding activity of endogenous SOX2. [P2W18O62]6− (PW) Wells-Dawson-type anion was the most effective at inhibiting proliferation in various cell line models of tamoxifen resistance. 10 µM PW also reduced cancer cell migration and invasion, as well as SNAI2 expression levels. Treatment of tamoxifen-resistant cells with PW impaired tumour formation by reducing CSC content, in a SOX2-dependent manner, which led to stem cell depletion in vivo. Mechanistically, PW induced formation of reactive oxygen species (ROS) and inhibited Bcl-2, leading to the death of tamoxifen-resistant cells. PW-treated tamoxifen-resistant cells showed restored sensitivity to tamoxifen. Conclusions: Together, these observations highlight the potential use of PW as a SOX2 inhibitor and the therapeutic relevance of targeting SOX2 to treat tamoxifen-resistant breast cancer. [ABSTRACT FROM AUTHOR]

The nitrogen‐rich molybdenum nitrides (N/Mo > 1) are promising for water electrolysis due to their increased activity and antioxidant ability. However, a higher temperature is needed in the usual synthesis for introducing more N, leading to the formation of large particles and the difficulty in controlling the morphology, thus limiting their catalytic performance. Here, a new strategy is reported based on the synergy of internal/external N sources (INS and ENS) toward Mo5N6‐based catalysts at a decreased temperature of 450 °C. The PMo12 clusters and Ni2+ (Co2+) are first combined with 2‐methylimidazole/melamine (INS) to give a flower‐like assembly. The subsequent pyrolysis under NH3 flow (ENS) gives the flowers composed of small Mo5N6/Ni (Co) heterojunctional particles that can expose more surface sites with an optimized electronic structure. The Mo5N6/Ni exhibits good HER activity close to Pt/C, and Mo5N6/Co shows superior OER performance to IrO2. The Mo5N6/Ni||Mo5N6/Co cell drives overall water splitting (OWS) at a low voltage of 1.397/1.74 V to achieve a current density of 10/100 mA cm−2 in the 1.0 M KOH. An anion exchange membrane water electrolyzer (AEMWE) based on the catalysts can achieve a current density of 450 mA cm−2 at 1.8 V with a long‐term stability of 120 h. [ABSTRACT FROM AUTHOR]

The self‐assembly of inorganic nanocrystals offers an efficient way for the fabrication of functional materials. However, it is still challenging for the construction of multidimensional nanostructures with controllable shapes, compositions and functions. Here, a series of heterostructures in different dimensions by surface modification of polyoxometalate (POM) clusters is developed. Three kinds of POM clusters (phosphomolybdic acid (PMA), phosphotungstic acid (PTA) and silicotungstic acid (STA) and five kinds of metal oxides (TiO2, VOx, La2O3, In2O3 and Gd2O3) can be used as building blocks, and a class of 1D, 2D and 3D heterostructures can be achieved by the control of surface ligand coverage. Compared with individual building blocks and other cluster‐based superstructures, TiO2‐PMA superstructures exhibit enhanced catalytic activity toward thioether oxidations, which is attributed to the electron transfer between TiO2 and POM clusters. [ABSTRACT FROM AUTHOR]

An organic–inorganic hybrid polyoxometalate (POM) CoPMoV [PMoVI8VIV4VV2O42][Co(Phen)2(H2O)]2[TEA]2•H3O•3H2O (Phen = 1,10-phenanthroline, TEA = triethylamine) prepared by hydrothermal synthesis was explored as a heterogeneous catalysts to remove methylene blue (MB) through Fenton-like reaction and catalytic reduction. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) were employed to characterize CoPMoV. The MB removal rates for the Fenton-like reaction and the catalytic reduction were 91.6% (120 min) and 97.5% (2 min), respectively, under optimum conditions. CoPMoV demonstrated excellent stability and recyclability in the Fenton-like reaction and catalytic reduction, which was confirmed by 5 cycle tests. Plausible mechanisms for MB degradation and reduction have also been proposed. Benefiting from the excellent redox properties of cobalt and [PMoVI8VIV4VV2O42]5− anion, CoPMoV could act as a Fenton-like and reductive catalyst for the removal of MB. This study provides a green and facile strategy to design POM-based organic–inorganic material for dye wastewater treatment via oxidation and reduction. [ABSTRACT FROM AUTHOR]

Based on the principle of molecular design and self-assembly, a novel rare earth based arsenotungstate was obtained by introducing rare earth LaⅢ ions into the lacunary polyoxotungstates clusters with vacancy structure by one-pot method with Na2 WO4 ·2H2 O, NaAsO2 and LaCl3 ·6H2 O as the main materials. The structure and composition of this complex was confirmed by single-crystal X-ray diffraction, X-ray powder diffraction (PXRD), infrared spectroscopy (IR) and so on. The single crystal X-ray diffraction results show that the complex is in the monoclinic system, C2/c space group, and with the cell parameters of a =3.595 56(14) nm, b =1.222 48(4) nm, c =2.247 34(9) nm, β = 117.117 0(10)°, V =8.792 3(6) nm3, Z =4. The molecular formula of this compound is [(CH3)2 NH2]8 H3. 56 [{LaO(H2 O)2 }{WO(H2 O)}{W0. 24 (H2 O)2 } {AsW9 O33 }2]. And the polyoxoanion [{LaO(H2 O)2 }{WO(H2 O)}{W0. 24 (H2 O)2 }{AsW9 O33 }2]11. 56 - shows a novel sandwich type structure, which can be simply described as two trilacunary Keggin type{AsW9 O33 } units are linked by a {LaO(H2 O)2 } segment, a {WO(H2 O)} segment and a {W0. 24 (H2 O)2 } segment. Catalytic degradation property of this compound for Rhodamine-B was further inverstigated. The results demonstrate that the compound shows good photocatalytic activity under the condition of 300 W Hg lamp irradiation, and the degradation efficiency reaches to 74%. [ABSTRACT FROM AUTHOR]

In this work, a novel heterogeneous catalyst consisting of peroxophosphotungstate, microporous MOF-808, and mesoporous SBA-15 was synthesized, characterized, and used to remove sulfides from model fuel. The prepared material, PW4@MOF-808@SBA-15, exhibits excellent catalytic activity with a desulfurization efficiency of 99.8% in 60 min for multicomponent simulated fuel, and the desulfurization rate can reach more than 90% after ten consecutive cycles. The excellent catalytic activity and reusability are attributed to the hierarchically porous hybrid material MOF-808@SBA-15, which can effectively encapsulate PW4 and provide a site for the oxidation of sulfides. [ABSTRACT FROM AUTHOR]

Polyelectrolytes are charged polymers comprising macromolecules in which substantial portions of the constituent units contain cationic (e.g., pyridinium, ammonium) or anionic (e.g., sulfonate, carboxylate) groups, which possess special functions from the features of counterions, such as dissociation to charged species, mechanical stability, phase behavior, etc. Therefore, functional polyelectrolytes have been widely applied in many fields. In this perspective, we present some progresses in the studies of poly(polyoxometalate)s, denoted as poly(POM)s, as a kind of new charged polymers/polyelectrolytes, by covalent bonding between the inorganic polyoxometalate (POM) clusters and the organic polymer chains. According to the distinct positions of POMs in polymer chain and functions of poly(POM)s, they are divided into the following four categories: crosslinked poly(POM); side-chain poly(POM); backbone poly(POM), including poly(POM)-conjugated polymer hybrid and block poly(POM)-polymer; and POM-based covalent organic framework (PCOF). This perspective introduces the synthesis methods of poly(POM) polyelectrolytes and their macromolecular and aggregate structural characteristics, while also focusing on their properties and functions. Their application areas include catalysis, thermal resistance, optical functions, fuel cells and batteries, etc. [ABSTRACT FROM AUTHOR]

It is urgent to remove various pollutants from the water environment. Therefore, an inorganic–organic hybrid polyoxometalate (POM) [PMoVI6MoV2VIV8O44{Co(2,2′‐bipy)2(H2O)}4]‐[PMoVI4MoV4VIV8O44{Co(2,2′‐bipy)2(H2O)}2]·4H2O (PMoVCo) was fully characterized by XRD, XPS, FTIR, SEM, BET and zeta potential techniques, and applied for the catalytic reduction of hazardous methylene blue (MB), methyl orange (MO), rhodamine B (RhB), Cr (VI) and 4‐nitrophenol (4‐NP) in aqueous media over NaBH4 under mild condition. The removal ratios were 99.6% (MB, 2.5 min), 97.0% (MO, 3.0 min), 92.5% (RhB, 2.0 min), 89.2% (Cr (VI), 2.0 min) and 89.6% (4‐NP, 2.5 min), respectively. The pseudo‐first‐order rate constants of the reactions were 1.992 min−1 (MB), 0.810 min−1 (MO), 1.768 min−1 (RhB), 1.186 min−1 (Cr (VI)) and 0.934 min−1 (4‐NP), respectively. Additionally, PMoVCo exhibited satisfactory catalytic activity for the photo‐Fenton‐like degradation of MB at neutral pH under visible light irradiation with a degradation rate up to 99.9% in 480 min. The results of the recycling experiment prove that PMoVCo has high catalytic reusability. Moreover, the possible mechanisms of the catalytic reduction and degradation processes were proposed. The catalytic activities of PMoVCo are better than other inorganic–organic hybrid POMs. All the results of this study indicate that PMoVCo has the potential to be a satisfactory catalyst for wastewater remediation via reduction or photocatalytic degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] Zinc metal anodes in aqueous electrolytes commonly face challenges such as dendrite growth and undesirable side reactions, limiting their application in the field of aqueous zinc-ion batteries (AZIBs) for energy storage. Drawing inspiration from industrial practices involving molybdenum salt solutions for metal modification, a polyoxometalate solution was formulated as a passivation solution for zinc anodes (referred to as MO solution). The formed passivation layer, referred to as the MO layer, exhibited a uniform and protective nature with a thickness of approximately 10 μm. The experimental results demonstrated that this passivation layer effectively suppressed side reactions at the zinc anode interface, as evidenced by lower corrosion current density for MO-Zn anodes. Additionally, the newly plated Zn was uniformly deposited atop the MO layer, ensuring coating integrity and inhibiting dendrite growth. As a result, under more demanding conditions such as a larger current of 8 mA cm−2, the MO-Zn anode displayed an extended cycle life exceeding 420 h in a symmetric battery, with an overpotential as low as 98 mV. This performance significantly outperformed that of commercially available pure Zn foils (with a cycle life of 60 h and an overpotential of 192 mV). Notably, a self-made Na-doped V 2 O 5 served as the cathode (referred to as NaVO), forming the MO-Zn//NaVO full battery. Even under high current test conditions of 2 A/g, the specific capacity of the MO-Zn//NaVO full battery remained substantial at 152.83 mAh/g after 1000 cycles. Furthermore, pouch batteries assembled with NaVO//MO-Zn successfully illuminated small bulbs. This study offers a viable optimization strategy for AZIB anodes and demonstrates the potential of using polyoxometalate solution for etching zinc anodes to inhibit dendrite growth and interfacial corrosion of zinc metal anodes. [ABSTRACT FROM AUTHOR]

Dimensional regulation in polyoxometalates is an effective strategy during the design and synthesis of polyoxometalates-based high proton conductors, but it is not available to date. Herein, the precise regulation of dimensionality has been realized in an unprecedented gigantic molybdenum blue wheel family featuring pentagonal {(W)Mo5} motifs through optimizing the molar ratio of Mo/W, including [Gd2Mo124W14O422(H2O)62]38− (0D-{Mo124W14}, 1), [Mo126W14O441(H2O)51]70− (1D-{Mo126W14}n, 2), and [Mo124W14O430(H2O)50]60− (2D-{Mo124W14}n, 3). Such important {(W)Mo5} structural motif brings new reactivity into gigantic Mo blue wheels. There are different numbers and sites of {Mo2} defects in each wheel-shaped monomer in 1–3, which leads to the monomers of 2 and 3 to form 1D and 2D architectures via Mo–O–Mo covalent bonds driven by {Mo2}-mediated H2O ligands substitution process, respectively, thus achieving the controllable dimensional regulation. As expected, the proton conductivity of 3 is 10 times higher than that of 1 and 1.7 times higher than that of 2. The continuous proton hopping sites in 2D network are responsible for the enhanced proton conductivity with lower activation energy. This study highlights that this dimensional regulation approach remains great potential in preparing polyoxometalates-based high proton conductive materials. [ABSTRACT FROM AUTHOR]

Abstract Background Increased cancer stem cell (CSC) content and SOX2 overexpression are common features in the development of resistance to therapy in hormone-dependent breast cancer, which remains an important clinical challenge. SOX2 has potential as biomarker of resistance to treatment and as therapeutic target, but targeting transcription factors is also challenging. Here, we examine the potential inhibitory effect of different polyoxometalate (POM) derivatives on SOX2 transcription factor in tamoxifen-resistant breast cancer cells. Methods Various POM derivatives were synthesised and characterised by infrared spectra, powder X-ray diffraction pattern and nuclear magnetic resonance spectroscopy. Estrogen receptor (ER) positive breast cancer cells, and their counterparts, which have developed resistance to the hormone therapy tamoxifen, were treated with POMs and their consequences assessed by gel retardation and chromatin immunoprecipitation to determine SOX2 binding to DNA. Effects on proliferation, migration, invasion and tumorigenicity were monitored and quantified using microscopy, clone formation, transwell, wound healing assays, flow cytometry and in vivo chick chorioallantoic membrane (CAM) models. Generation of lentiviral stable gene silencing and gene knock-out using CRISPR-Cas9 genome editing were applied to validate the inhibitory effects of the selected POM. Cancer stem cell subpopulations were quantified by mammosphere formation assays, ALDEFLUOR activity and CD44/CD24 stainings. Flow cytometry and western blotting were used to measure reactive oxygen species (ROS) and apoptosis. Results POMs blocked in vitro binding activity of endogenous SOX2. [P2W18O62]6− (PW) Wells-Dawson-type anion was the most effective at inhibiting proliferation in various cell line models of tamoxifen resistance. 10 µM PW also reduced cancer cell migration and invasion, as well as SNAI2 expression levels. Treatment of tamoxifen-resistant cells with PW impaired tumour formation by reducing CSC content, in a SOX2-dependent manner, which led to stem cell depletion in vivo. Mechanistically, PW induced formation of reactive oxygen species (ROS) and inhibited Bcl-2, leading to the death of tamoxifen-resistant cells. PW-treated tamoxifen-resistant cells showed restored sensitivity to tamoxifen. Conclusions Together, these observations highlight the potential use of PW as a SOX2 inhibitor and the therapeutic relevance of targeting SOX2 to treat tamoxifen-resistant breast cancer.

The bimetallic sulfide in-situ encapsulated by C 3 N 4 walls (CoMoS@CN) was fabricated by using the well-designed POM superlattice assembly as precursor and performed efficiently for electrocatalytic hydrogen production, capable of achieving low overpotentials, high selectivity and Faradaic efficiency of nearly 100 % in both acidic and alkaline media. [Display omitted] • Construction of CoMoS@CN using POM superlattice assembly as precursor. • Enhanced specific surface area, charge transfer kinetics and HER activity. • Efficient and stable hydrogen production in both acidic and alkaline conditions. Over the years, polyoxometalates (POMs) have been advocated as one of the most promising classes of molecular preassembly platform for the fabrication of highly efficient metal sulfide electrocatalysts. However, designing POMs-derived metal sulfides with high intrinsic activity, good site accessibility and structural stability for both acidic and alkaline hydrogen evolution reaction (HER) remains a great challenge because of the self-aggregation and random distribution of traditional POM precursors. Herein, we have designed a bimetallic sulfide eventually encapsulated by C 3 N 4 walls (CoMoS@CN) for efficient HER based on a simple hydrothermal and subsequent high-temperature vulcanization using the well-designed POM superlattice assembly as precursor. The organized superlattice structure with long-range ordered arrangements of POM units provide chance to prevent the agglomeration of metal sites. The in-situ formed exterior C 3 N 4 protective wall can accelerate the electron transfer and protect catalyst from chemical corrosion in different electrolyte. The merits combining with a large specific surface area enable CoMoS@CN with remarked HER performance of low overpotentials of 164 and 95 mV at 10 mA cm−2 in acidic and alkaline conditions. Such results are better than that of p -CoMoS@CN synthesized by pyrolysis of the corresponding physical mixtures and other comparative single metal sulfides. [ABSTRACT FROM AUTHOR]

The rational design of Pt/Zn 0.2 Cd 0.8 S/Cs 3 PW 12 O 40 Z-type heterojunction ternary composites, under the synergistic effect of photochromic effect-Z-type heterojunction-helper catalyst Pt, effectively mitigates photocorrosion and significantly improves the efficiency of photocatalytic hydrogen production. [Display omitted] • Unique photochromic effect effectively mitigates photocorrosion. • The construction of a Z-type heterojunction promotes carrier separation. • Schottky junction can accelerate charge transfer. • The optimal hydrogen evolution rate of ternary composite can reach 10 mmol/g/h. Catalysts are key components in the photocatalytic hydrogen precipitation process. However, commonly used catalysts such as sulfides, suffer from severe photogenerated carrier recombination and photocorrosion. To address this problem, in this work, Cs 3 PW 12 O 40 , polyoxometalates with reversible photochromic effect, and Zn 0.2 Cd 0.8 S with photocorrosivity are constructed to form a Z-type heterojunction to facilitate the separation of photogenerated carriers, and at the same time synergize with the unique photochromic effect of Cs 3 PW 12 O 40 to mitigate photocorrosion. Moreover, by introducing the co-catalyst Pt to form a Schottky barrier, which further promotes the separation of photogenerated carriers, the Pt/Zn 0.2 Cd 0.8 S/Cs 3 PW 12 O 40 Z-type heterojunction ternary composites were finally rationally designed and applied to photocatalytic hydrogen precipitation for the first time. The photocatalytic hydrogen precipitation rate of the optimal heterojunction composite was 10.4 mmol/g/h, and its apparent quantum efficiency at a single wavelength of 420 nm could reach 8.15 %. Therefore, this study provides a new strategy for alleviating the photocorrosion of sulfides and the application of polyoxometalates in photocatalytic hydrogen precipitation. [ABSTRACT FROM AUTHOR]

[Display omitted] Non-oxidative intercalation of graphite avoids damage to graphene lattices and is a suitable method to produce high-quality graphene. However, the yield of exfoliated graphene is low in this process due to the poor delamination efficiency of guest species. In this study, a Brønsted acid intercalation protocol is developed involving polyoxometalate (POM) clusters (H 6 P 2 W 18 O 62) as guests and intercalation of graphite is realized at the sub-nanometer scale. Theoretical simulation based on DFT elucidates the stepwise intercalation mechanism of Brønsted acid molecules and clusters. Unlike common molecules/ionic guests, intercalation of POM clusters induces large expansion and extensive donor–acceptor interactions among graphite interlayers. This significantly weakens the van der Waals forces and promotes exfoliation efficiency of graphene layers. The exfoliated graphene possesses outstanding features of large lateral size, thin thickness, and high purity, and shows excellent performance as the anode for high power sodium-ion batteries. This work proffers a new pathway toward non-oxidative intercalation of graphite for large-scale production of graphene. [ABSTRACT FROM AUTHOR]

A formaldehyde-phosphomolybdic acid battery is designed to simultaneously achieve the production of reduced phosphomolybdic acid with electricity and hydrogen generation, in which Cu x O nanowire arrays in-situ grown on Cu foam is used as an efficient porous electrode for the H 2 production from the electrooxidation of formaldehyde. And the reduced polyoxometalate can further act as an electron-coupled proton buffer for the decoupled hydrogen production from water electrolysis. The reported battery possesses an open circuit voltage of about 0.95 V with a peak power density of 8.0 mW cm−2. Multiple discharge experiments reveal that the Faradaic efficiency for the hydrogen production from anodic formaldehyde oxidation is sustained at ∼100%, and a repeatable current density curve of the hydrogen production with a theoretical maximum coulombic efficiency of 100% can be achieved by oxidizing the reduced phosphomolybdic acid, suggesting a good stability of the reported cell device for dual-decoupled hydrogen production. [Display omitted] • Cu x O nanowires with a co-existence of Cu+ and Cu0 species are grown on Cu foam. • It is an efficient catalyst for the electrooxidation of HCHO to H 2 production. • A formaldehyde-phosphomolybdic acid battery is designed. • Dual-decoupled hydrogen production is achieved with electricity generation. [ABSTRACT FROM AUTHOR]

Biomass valorisation over polyoxometalate‐based (POM) catalysts is a promising strategy for green and sustainable chemistry. In order to further improve such processes e. g. by using different additives, a better understanding of the chemical influence of various additives on the catalyst is paramount. The main objective of this study is to gain a deeper understanding of the effects caused by various additives on the catalytically active vanadium species in the selective aerobic oxidation of carbohydrates to formic acid (esters). After carefully choosing a suitable model system, the oxidation of glycolaldehyde using the heteropolyacid H5PV2Mo10O40 (HPA‐2) as a catalyst was studied in situ by Flow Nuclear magnetic resonance (FlowNMR) spectroscopy. These measurements allowed to identify the catalytically active isomer of the HPA‐2‐catalyst and to observe the influence of additives on the reaction kinetics in situ. These findings provide a good basis for further improving POM‐based catalytic aerobic oxidation of biomass. [ABSTRACT FROM AUTHOR]

A photocatalyzed formal (3+2) cycloaddition has been developed to construct original polysubstituted α‐SCF3 cyclopentanones in a regio‐ and diastereoselective manner. This building block approach leverages trifluoromethylthio alkynes and branched/linear aldehydes, as readily available reaction partners, in consecutive hydrogen atom transfers and C−C bond formations. Difluoromethylthio alkynes are also compatible substrates. Furthermore, the potential for telescoped reaction starting from alcohols instead of aldehydes was demonstrated, as well as process automatization and scale‐up under continuous microflow conditions. This prompted density functional theory (DFT) calculations to support a radical‐mediated cascade process. [ABSTRACT FROM AUTHOR]

The reasonable design of metal–organic framework (MOF)–derived nanomaterial has important meaning in increasing the enrichment efficiency in the study of protein phosphorylation. In this work, a polyoxometalate (POM) functionalized magnetic MOF nanomaterial (Fe3O4@MIL-125-POM) was designed and fabricated. The nanomaterial with multi-affinity sites (unsaturated metal sites and metal oxide clusters) was used for the enrichment of phosphopeptides. Fe3O4@MIL-125-POM had high-efficient enrichment performance towards phosphopeptides (selectivity, a mass ratio of bovine serum albumin/α-casein/β-casein at 5000:1:1; sensitivity, 0.1 fmol; satisfactory repeatability, ten times). Furthermore, Fe3O4@MIL-125-POM was employed to enrich phosphopeptides from non-fat milk digests, saliva, serum, and A549 cell lysate. The enrichment results illustrated the great potential of Fe3O4@MIL-125-POM for efficient identification of low-abundance phosphopeptides. [ABSTRACT FROM AUTHOR]

Developing non-noble metal-based electrocatalyst with high catalytic activity is essential for advancing hydrogen energy technologies. This study introduces a hydrothermal method for synthesizing order Ni(OH)2 nanosheets, with H3O40PW12 (denoted as PW12) loaded onto reduced graphene oxide (rGO) coated on nickel foam (referred to as PW12-Ni(OH)2/rGO). This method contrasts with the electrodeposition of Ni(OH)2, where PW12 is added to the synthetic system to direct the assembly and morphology of the Ni(OH)2 through a hydrothermal reaction. In this work, the nickel foam acts dual roles as both the substrate and the source of nickel for the formation of Ni(OH)2. The PW12-Ni(OH)2/rGO nanosheets, when successfully prepared and loaded onto the nickel foam (NF), exhibited superior electrocatalytic activity for the hydrogen evolution reaction (HER) in an alkaline electrolyte, achieving a current density of 10 mA·cm−2 at an overpotential of 69 mV. Furthermore, we endeavored to expand the application of this material towards the oxygen evolution reaction (OER) by preparing PW12-(Fe/Co)Ni(OH)2/rGO through the addition of metal cations. This nanocomposite displayed outstanding electrocatalytic activity in alkaline electrolytes, with a current density of 10 mA·cm−2 at an overpotential of 211 mV, and demonstrated excellent stability over a 50 h period in a 1 M KOH solution. The results presented in this paper offer an effective strategy for the preparation of polyoxometalate-based inorganic materials with diverse functionalities, applicable to both HER and OER. [ABSTRACT FROM AUTHOR]

In this work, Preyssler‐type POM (NH4)14[NaP5W30O110].44H2O (NH4P5W30), has been synthesised and its electrochemical behaviour in solution was examined at the surface of glassy carbon (GC) and gold electrodes. Furthermore, multilayer assemblies of NH4P5W30 POM were constructed onto the surfaces of GCE, gold electrode, and gold quartz electrode via the electrostatic Layer‐by‐Layer (LBL) technique employing polyethyleneimine as the cationic layer and POM as an anionic layer. Cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and electrochemical quartz crystal microbalance measurements (EQCM) were used to monitor the LBL assembly as the NH4P5W30 POM layer was being built. These techniques revealed significant differences in film growth. The multilayer film exhibited well‐defined redox couples associated with POM's tungsten‐oxo framework and showed surface‐confined behaviour up to 100 mVs−1 on both the GC and gold electrodes. The pH dependency and stability of the film were investigated. EIS demonstrated that when the POM layer was the outer layer, the layers were less conductive, and resistance increased as the number of layers increased. In addition, the charge transfer resistance values (Rct) for the layers were calculated. The solvation of ions into the film associated with POM redox activity was studied employing an in‐situ EQCM. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Self‐assembly of polyoxometalate (POM) clusters offers a viable method for constructing nanostructures with tailored properties. Over the past few decades, POMs‐based nanostructures of varying dimensions, such as nanowires, nanobelts, nanosheets, and other superstructures, have been constructed. Additionally, these nanostructures show broad prospects in optical, electrochemical, catalytic, and mechanical applications. Particularly noteworthy are surface modifications, such as surfactant encapsulation, which yield amphiphilic POMs. These modifications render the POMs compatible with organic systems, significantly broadening their morphological and functional applicability. This concept provides an overview of recent advancements in nanostructures based on self‐assembly of surfactant encapsulated POM clusters, encompassing one‐dimensional (1D), two‐dimensional (2D), and three‐dimensional (3D) structures. Through surfactant encapsulation, POM clusters can be rendered compatible with various solvents, facilitating the formation of hybrid assemblies with diverse morphologies and unique properties. The structures, formation mechanisms, and properties of these sub‐nanometer assemblies are discussed from both experimental and theoretical perspectives. This concept aims to provide a new insight into the design and fabrication of nanostructures based on POM clusters. [ABSTRACT FROM AUTHOR]

Two highly uniform heterometallic photo-catalysts afforded by polyoxometalate synthons realize ultra-efficient hydrogen evolution of 2873 μmol g-1h−1, approaching triple times that of CdS and nearly sextuple times that of MoS 2. [Display omitted] • Two new highly dispersed bimetallic/trimetallic sulfide materials were prepared. • Showing ultra-efficient photocatalytic hydrogen evolution. • The efficient hydrogen evolution can run up to 2873 μmol g-1h−1. • The photocatalytic performance is much higher than most similar photocatalysts. • Providing a promising direction for the development of efficient photocatalysts. MoS 2 -based materials have emerged as photoelectric semiconductors characterized by a narrow band gap, high capacity for absorbing visible light, and reduced H 2 adsorption energy comparable to Pt. These attributes render them appealing for application in photocatalytic hydrogen production. Despite these advantages, the widespread adoption of MoS 2 -based materials remains hindered by challenges associated with limited exposure to active sites and suboptimal catalytic hydrogen production efficiency. To address these issues, we have designed and synthesized a new class of highly dispersed bimetallic/trimetallic sulfide materials. This was achieved by developing polyoxometalate synthons containing Ni-Mo elements, which were subsequently reacted with thiourea and CdS. The resulting Ni 3 S 2 -MoS 2 and Ni 3 S 2 -MoS 2 -CdS materials achieve photocatalytic hydrogen production rates of 2770 and 2873 μmol g–1h−1, respectively. Notably, the rate of 2873 μmol g–1h−1 for Ni 3 S 2 -MoS 2 -CdS surpassed triple (3.23 times) the performance of CdS and nearly sextuple (5.77 times) that of single MoS 2. These materials outperformed the majority of MoS 2 -based photocatalysts. Overall, this study introduces a straightforward methodology for synthesizing bimetallic/trimetallic sulfides with enhanced photocatalytic H 2 evolution performance. Our findings underscore the potential of transition metal sulfide semiconductors in the realm of photocatalysis and pave the way for the development of more sustainable energy production systems. [ABSTRACT FROM AUTHOR]

Solar‐driven CO2 reduction and water oxidation to liquid fuels represents a promising solution to alleviate energy crisis and climate issue, but it remains a great challenge for generating CH3OH and CH3CH2OH dominated by multi‐electron transfer. Single‐cluster catalysts with super electron acceptance, accurate molecular structure, customizable electronic structure and multiple adsorption sites, have led to greater potential in catalyzing various challenging reactions. However, accurately controlling the number and arrangement of clusters on functional supports still faces great challenge. Herein, we develop a facile electrosynthesis method to uniformly disperse Wells‐Dawson‐ and Keggin‐type polyoxometalates on TiO2 nanotube arrays, resulting in a series of single‐cluster functionalized catalysts P2M18O62@TiO2 and PM12O40@TiO2 (M=Mo or W). The single polyoxometalate cluster can be distinctly identified and serves as electronic sponge to accept electrons from excited TiO2 for enhancing surface‐hole concentration and promote water oxidation. Among these samples, P2Mo18O62@TiO2‐1 exhibits the highest electron consumption rate of 1260 μmol g−1 for CO2‐to‐CH3OH conversion with H2O as the electron source, which is 11 times higher than that of isolated TiO2 nanotube arrays. This work supplied a simple synthesis method to realize the single‐dispersion of molecular cluster to enrich surface‐reaching holes on TiO2, thereby facilitating water oxidation and CO2 reduction. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a devastating neurodegenerative disease that affects ∼50 million people globally. The accumulation of amyloid-β (Aβ) plaques, a predominant pathological feature of AD, plays a crucial role in AD pathogenesis. In this respect, Aβ has been regarded as a highly promising therapeutic target for AD treatment. Polyoxometalates (POMs) are a novel class of metallodrugs being developed as modulators of Aβ aggregation, owing to their negative charge, polarity, and three-dimensional structure. Unlike traditional discrete inorganic complexes, POMs contain tens to hundreds of metal atoms, showcasing remarkable tunability and diversity in nuclearities, sizes, and shapes. The easily adjustable and structurally variable nature of POMs allows for their favorable interactions with Aβ. This mini-review presents a balanced overview of recent progress in using POMs to mitigate amyloidosis. Clear correlations between anti-amyloid activities and structural features of POMs are also elaborated in detail. Finally, we discuss the current challenges and future prospects of POMs in combating AD. [ABSTRACT FROM AUTHOR]

Polyoxometalate (POM)-based ionic liquids (POM-ILs) are gaining increasing attention due to their diverse structures and functionalities. POMs in POM-ILs not only act as essential structural building blocks but also play a crucial role in their functional performance. With the incorporation of POMs, POM-ILs find applications in various fields such as chemical catalysis, energy science, materials science, sensors, and more. The abundant availability of POMs and other building blocks in POM-ILs, along with their versatile combination possibilities, present promising opportunities for the future. Rather than focusing solely on discovering new structures of POM-ILs, current developments in this field emphasize exploring their functions, leading to the emergence of numerous new applications. Summarizing these advancements aids in understanding the latest trends and facilitates rapid evolution. This review examines the recent five years’ worth of results to analyze the new functions of POM-ILs, categorizing them based on their unique characteristics. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs)-based nanoreactors have attracted broad interest in many fields due to their void-confinement effects. However, the inherent drawback of conventional nanoreactors is the lack of internal active sites, which limits their widespread utilization. Herein, we report the construction of hierarchical COF (EB-TFP) nanoreactor with pre-synthesized polyoxometalates (POM, [PV2W10O40]5− (PV2W10)) clusters encapsulated inside of COF (POM@COF). PV2W10@EB-TFP anchors nucleophilic-group (Br− ions) and PV2W10 anion cluster within the COF framework via electrostatic interactions, which not only simplifies the reaction system but also enhances catalytic efficiency. The reaction performance of the PV2W10@EB-TFP nanoreactor can be tuned to achieve excellent catalytic activity in CO2 cycloaddition reaction (CCR) for ∼ 97.63% conversion and ∼ 100% selectivity under visible light irradiation. A mechanistic study based on density functional theory (DFT) calculations and in-situ characterization was also carried out. In summary, we have reported a method for achieving the uniform dispersion of POM single clusters into COF nanoreactor, demonstrating the potential of POM@COF nanoreactor for synergistic photothermal catalytic CO2 cycloaddition. [ABSTRACT FROM AUTHOR]

Novel materials with highly synchronized electrochromic (EC) and energy storage properties are needed to simultaneously visualize and quantify the real-time charge state of energy storage devices. Herein, a film was prepared by the Layer-by-Layer assembly of W 18 O 49 nanowires and a Preyssler-type polyoxometalate (POM) [P 5 W 30 O 110 ]15− (P 5 W 30). The introduction of amorphous POM decreased the band gap to 2.54 eV, which greatly facilitated the synergy between the EC and charge storage properties. Driven under a low voltage of −0.6 V, this W 18 O 49 /P 5 W 30 composite film displayed strong and reversible changes in its optical absorbance in both the visible and near-infrared regions, and it also showed the typical pseudocapacitance behavior with an area capacitance of 34.71 mF cm−2. Moreover, this film was able to simultaneously quantify and visualize its own energy storage state and photothermal conversion in real time by significant color changes (maximum chromaticity difference: 72.44) and high absorbance changes (1.11 at 650 nm and 1.11 at 1200 nm). In addition, a gel EC supercapacitor based on the W 18 O 49 /P 5 W 30 film as cathode and NiO film as anode exhibited an absorbance variation up to 0.75 and an area capacitance as high as 4.42 mF cm−2, and it successfully powered a light emitting diode using the stored electrical energy. This work not only broadens the application scope of POM-based EC materials but also provides a feasible design strategy for next-generation smart energy storage devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Glaser‐coupled synthesized 1,3‐diyne can participate in the generation of conjugated polymers and is now widely used in organic and polymer synthesis. Currently, the catalyst in coupling are mostly based on the complexation of noble metals with complex organic ligands, which inevitably increases the research cost and storage difficulty. However, polyoxometalates (POMs), with acidic and redox properties, can be used as an excellent inorganic ligands with low cost and easy storage. In this work, we have synthesized copper catalyst 1, (NH4)4[CuMo6O18(OH)6] with polyoxometalates as inorganic ligands in a facile way and applied them in the coupling of alkynes to obtain (non)symmetrical conjugated 1,3‐diynes in high yields without bases, finally proposing a reasonable reaction path. In addition, the catalyst showed good tolerance to a variety of different groups, further demonstrating its excellent catalytic activity. It is worth mentioning that the catalyst maintained its good structure and activity after six cycles, demonstrating its promising potential for industrial applications. Thus, this paper provides a new strategy for the preparation of (un)symmetrical diynes using polyoxometalates of Cu as catalyst, and also demonstrates the potential of multi‐acid catalyst for organocatalytic applications. [ABSTRACT FROM AUTHOR]

Lanthanide elements such as europium exhibit distinctive emissions due to the transitions of inner-shell 4f electrons. Inorganic materials containing lanthanide elements have been widely used as phosphors in conventional displays. The hybridization of lanthanide ions with organic components enables to control of the material's shapes and properties and broadens the possibility of lanthanide compounds as inorganic–organic materials. Lanthanide ion-containing polyoxometalate anions (Ln-POM) are a promising category as an inorganic component to design and synthesize inorganic–organic hybrids. Several inorganic–organic Ln-POM systems have been reported by hybridizing with cationic surfactants as luminescent materials. However, single-crystalline ordering has not been achieved in most cases. Here, we report syntheses and structures of inorganic–organic hybrid crystals of lanthanide-based POM and bolaamphiphile surfactants with two hydrophilic heads in one molecule. An emissive decatungstoeuropate ([EuW10O36]9−, EuW10) anion was employed as a lanthanide source. The bolaamphiphile counterparts are 1,8-octamethylenediammonium ([H3N(CH2)8NH3]2+, C8N2) and 1,10-decamethylenediammonium ([H3N(CH2)10NH3]2+, C10N2). Both hybrid crystals of C8N2-EuW10 and C10N2-EuW10 were successfully obtained as single crystals, and their crystal structures were unambiguously determined using X-ray diffraction measurements. The photoluminescence properties of C8N2-EuW10 and C10N2-EuW10 were investigated by means of steady-state and time-resolved spectroscopy. The characteristic emission derived from the EuW10 anion was retained after the hybridization process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Molecular Science is the property of Journal of Molecular Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Molecular Science is the property of Journal of Molecular Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tetraphenylethene and its derivatives have become increasingly attractive as aggregation-induced emission luminogens (AIEgens) due to their superior luminescence efficiency and low contamination. In this paper, a tetraphenylethene derivative (4,4′,4″,4‴-(ethene-1,1,2,2-tetrayltetrakis-(benzene-4,1-diyl)) tetrakis-(1-allylpyridin-1-ium), TPE-1) synthesized with unique fluorescent properties, was integrated into a fluorescent nanocomposite with polyoxometalate (Na9[Eu-(W5O18)2]·32H2O, EuW10) in an aqueous solution using an ionic self-assembly strategy. The TPE-1/EuW10 nanocomposite is composed of spherical particles with a uniform particle size of about 40 nm, and compared with the original material TPE-1, its quantum yield grows from 18.27% to 39.88%. The experimental results suggest that the negatively charged groups of EuW10 may interact electrostatically with the positively charged nitrogen atoms of TPE-1, leading to the aggregation of TPE-1 molecules to enhance the fluorescence. Mixing the TPE-1/EuW10 nanocomposite with commercially available blue and green phosphor can yield a white emitting phosphor with the CIE coordinate of (0.33, 0.34), which is close to the standard white light. This ionic self-assembly strategy of TPE-1 and EuW10 with easy preparation is of great significance for the simple construction of an AIE light-emitting system applicable to optoelectronic devices. [ABSTRACT FROM AUTHOR]