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A new Co4-added polyoxometalate (CoAP) Cs4[(Co(H2O)5)2{(μ2-Co(H2O)4)2Co4(H2O)2(B-α-GeW9O34)2}]·6H2O (1) has been made using a lacunary directing strategy under hydrothermal conditions. Single-crystal X-ray diffraction analysis demonstrated that 1 is a one-dimensional (1D) chain, in which CoAP is linked by cobalt-oxygen octahedra to form a 1D structure with excellent chemical stability. The visible light-driven H2 evolution test demonstrated that 1 has high activity, with an H2 evolution rate of 1485.95 μmol h−1 g−1. PXRD and FT-IR tests demonstrated that compound 1 exhibits excellent heterogeneous catalytic stability. [ABSTRACT FROM AUTHOR]

A new noncentrosymmetric strontium borate, P1‐Sr2[B5O8(OH)]2 ⋅ [B(OH)3] ⋅ H2O (1), has been synthesized under the hydrothermal condition. The P1‐Sr2[B5O8(OH)]2 ⋅ [B(OH)3] ⋅ H2O shows a layered B−O network with 9‐ring windows in the ab plane. Sr2+ cations, H3BO3, and H2O molecules are located in the voids of layers and interlayers, respectively. The P1‐Sr2[B5O8(OH)]2 ⋅ [B(OH)3] ⋅ H2O is the first synthetic phase of veatchite, while the other three polymorphs are found in different natural minerals. This strontium borate is a potential deep‐ultraviolet‐transparent nonlinear‐optical (NLO) crystal whose second‐harmonic‐generation (SHG) intensity is 1.7 times that of KH2PO4 (KDP) and is phase‐matchable. The short wavelength cutoff edge of compound 1 is below 190 nm. Density functional theory (DFT) calculations show that the B−O units are responsible for the nonlinear optical property. [ABSTRACT FROM AUTHOR]

Two structurally new Lindqvist hexaniobate-templated silver thiolate clusters, [Nb6O19@Ag45(iPrS)23(CH3COO)14] (Ag45) and (H3O)4[Nb6O19@Ag41KS2.5O2(H2O)7.5(iPrS)24(CH3COO)5] (Ag41), were synthesized using a facile one-pot solvothermal approach. Single crystal X-ray diffraction analyses revealed the presence of a classical Lindqvist-type [Nb6O19]8− anion template, with iPrS− and CH3COO− surface-protecting ligands in both silver clusters, which can further form two-dimensional Ag45 assembly and one-dimensional Ag41 chain packing structures. Both Ag45 and Ag41 clusters exhibited intriguing photothermal conversion properties and temperature-dependent emission behavior. [ABSTRACT FROM AUTHOR]

A quinoline-based covalent organic framework (N^N)-Q-COF was constructed with chemically stable networks and (N^N)-sites. Its coordination bond with Ir(C^N)2(N^N) units generated new entities with exciting photophysical properties; particularly, the incorporation of a coumarin ligand greatly elevated its properties to a higher level. The further anchoring of NiCl2 produced structures merging both photoredox and organometallic catalysts, resulting in excellent photocatalytic activities in C–S and C–N cross-coupling synthesis. The organic integration of Ir(C^N)2(N^N), NiCl2, and COFs and the advantages of COF networks were responsible for this transcendent dual catalysis. The chemical stability of Q-COFs and the coordination anchoring of Ir(C^N)2(N^N) and NiCl2 enabled its recycling and reuse with no reduction in catalytic performance. [ABSTRACT FROM AUTHOR]

Polyoxometalate-based nanocomposites with electrocatalytic activity have been applied in hydrogen evolution reactions (HER). Seawater as the main water resource on the earth should be developed as the water electrolysis to prepare high-purity hydrogen. In this paper, we used two synthesis strategies to prepare the nanocomposite Co4-POM@Co-PGDY (Co4-POM: the Kegging-type microcrystals of K10[Co4(PW9O34)2] and Co-PGDY: cobalt-porphyrin linked graphdiyne) with excellent activity for HER. Co-PGDY as the porous material is applied not only as the protection of microcrystals towards the metal ion in seawater but also as the co-electrocatalyst of Co4-POM. Co4-POM@Co-PGDY exhibits excellent HER performance in seawater electrolytes with low overpotential and high stability at high density. Moreover, we have observed a key H3O+ intermediate emergence on the surface of nanocomposite during hydrogen evolution process in seawater by Raman synchrotron radiation-based Fourier transform infrared (SR-FTIR). The results in this paper provide an effective strategy for preparing polyoxometalate-based electrocatalysts with high-performance toward hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

The syntheses of atomically precise silver (Ag) clusters stabilized by multidentate lacunary polyoxometalate (POM) ligands have been emerging as a promising but challenging research direction, the combination of redox‐active POM ligands and silver clusters will render them unexpected geometric structures and catalytic properties. Herein, we report the successful construction of two structurally‐new lacunary POM‐stabilized Ag clusters, TBA6H14Ag14(DPPB)4(CH3CN)9[Ag24(Si2W18O66)3] ⋅ 10CH3CN ⋅ 9H2O ({Ag24(Si2W18O66)3}, TBA=tetra‐n‐butylammonium, DPPB=1,4‐Bis(diphenylphosphino)butane) and TBA14H6Ag9Na2(H2O)9[Ag27(Si2W18O66)3] ⋅ 8CH3CN ⋅ 10H2O ({Ag27(Si2W18O66)3}), using a facile one‐pot solvothermal approach. Under otherwise identical synthetic conditions, the molecular structures of two POM‐stabilized Ag clusters could be readily tuned by the addition of different organic ligands. In both compounds, the central trefoil‐propeller‐shaped {Ag24}14+ and {Ag27}17+ clusters bearing 10 delocalized valence electrons are stabilized by three C‐shaped {Si2W18O66} units. The femtosecond/nanosecond transient absorption spectroscopy revealed the rapid charge transfer between {Ag24}14+ core and {Si2W18O66} ligands. Both compounds have been pioneeringly investigated as catalysts for photocatalytic CO2 reduction to HCOOH with a high selectivity. [ABSTRACT FROM AUTHOR]

A new Co 4 -added polyoxometalate (CoAP) Cs 4 [(Co(H 2 O) 5 ) 2 {(μ 2 -Co(H 2 O) 4 ) 2 Co 4 (H 2 O) 2 (B-α-GeW 9 O 34 ) 2 }]·6H 2 O (1) has been made using a lacunary directing strategy under hydrothermal conditions. Single-crystal X-ray diffraction analysis demonstrated that 1 is a one-dimensional (1D) chain, in which CoAP is linked by cobalt-oxygen octahedra to form a 1D structure with excellent chemical stability. The visible light-driven H 2 evolution test demonstrated that 1 has high activity, with an H 2 evolution rate of 1485.95 μmol h -1 g -1 . PXRD and FT-IR tests demonstrated that compound 1 exhibits excellent heterogeneous catalytic stability.

A new noncentrosymmetric strontium borate, P1-Sr 2 [B 5 O 8 (OH)] 2  ⋅ [B(OH) 3 ] ⋅ H 2 O (1), has been synthesized under the hydrothermal condition. The P1-Sr 2 [B 5 O 8 (OH)] 2  ⋅ [B(OH) 3 ] ⋅ H 2 O shows a layered B-O network with 9-ring windows in the ab plane. Sr 2+ cations, H 3 BO 3 , and H 2 O molecules are located in the voids of layers and interlayers, respectively. The P1-Sr 2 [B 5 O 8 (OH)] 2  ⋅ [B(OH) 3 ] ⋅ H 2 O is the first synthetic phase of veatchite, while the other three polymorphs are found in different natural minerals. This strontium borate is a potential deep-ultraviolet-transparent nonlinear-optical (NLO) crystal whose second-harmonic-generation (SHG) intensity is 1.7 times that of KH 2 PO 4 (KDP) and is phase-matchable. The short wavelength cutoff edge of compound 1 is below 190 nm. Density functional theory (DFT) calculations show that the B-O units are responsible for the nonlinear optical property., (© 2024 Wiley-VCH GmbH.)

Two metal borate-carbonates, M 6 [Cd 2 (CO 3 ) 2 (B 12 O 18 )(OH) 6 ] [M = K ( 1 ), Rb ( 2 )], were obtained under surfactant-thermal conditions. In 1 and 2 , each cyclic [(B 12 O 18 )(OH) 6 ] 6- anion captures two CdCO 3 in two sides of the rings and finally forms the unusual (CdCO 3 ) 2 @[(B 12 O 18 )(OH) 6 ] cluster. Both 1 and 2 show moderate birefringence. Density functional theory calculations indicate that carbonate groups have a major contribution to electron-related optical transition.

The development of effective and novel flame retardants has been attracting considerable attention in extenuating the fire threat of flammable polymer materials including the widely-used epoxy resins. In this work, we pioneeringly report the construction of transition-metal-substituted polyoxometalate-ionic liquids (tmsPOM-ILs) as effective flame retardants, which consist of tetra-metal-containing POMs ([M 4 (H 2 O) 2 (PW 9 O 34 ) 2 ] 10- , M 4 P 2 , M = Ni, Cu) anions and tetra- n -heptylammonium [( n -C 7 H 15 ) 4 N + , THPA] cations. The resulting tmsPOM-ILs exhibited remarkably improved fire-safety of the epoxy resin (EP) matrix and even at a loading amount of as low as 3 wt%, the flame retardancy efficiency was even higher than that of commercial flame retardants (aluminum hydroxide (ATH), triphenyl phosphate (TPP), and decabromodiphenyl ethane (DBDPE)). Physicochemical and mechanistic studies revealed that the remarkable flame retardancy performance of the tmsPOM-ILs reported is due to their excellent epoxy matrix compatibility and remarkable catalytic charring ability. This work opens up a brand-new research direction of developing next-generation compatible and effective tmsPOM-based molecular flame retardants at the molecular level.

Innovative surface-protecting ligands are in constant demand due to their crucial role in shaping the configuration, property, and application of gold nanoclusters. Here, the unprecedented O -ethyl dithiocarbonate (DTX)-stabilized atomically precise gold nanoclusters, [Au 25 (PPh 3 ) 10 (DTX) 5 Cl 2 ] 2+ ( Au 25 DTX -Cl ) and [Au 25 (PPh 3 ) 10 (DTX) 5 Br 2 ] 2+ ( Au 25 DTX -Br ), were synthesized and structurally characterized. The introduction of bidentate DTX ligands not only endowed the gold nanocluster with unique staggered Au 25 nanorod configurations but also generated the symmetry breaking from the D 5d geometry of the Au 25 kernels to the chiral D 5 configuration of the Au 25 molecules. The chirality of Au 25 nanorods was notably revealed through single-crystal X-ray diffraction, and chiral separation was induced by employing chiral DTX ligands. The staggered configurations of Au 25 nanorods, as opposed to eclipsed ones, were responsible for the large red shift in the emission wavelengths, giving rise to a promising near-infrared II (NIR-II, >1000 nm) phosphorescence. Furthermore, their performances in photocatalytic sulfide oxidation and electrocatalytic hydrogen evolution reactions have been examined, and it has been demonstrated that the outstanding catalytic activity of gold nanoclusters is highly related to their stability.

Covalent organic frameworks (COFs) and their applications in photocatalysis have been extensively studied, but the instability of imine-linked COFs is an important factor limiting their performance. In this work, two imine-linked COFs were successfully converted to amide-linked COFs through post synthetic modification (PSM). The oxidized COFs presented lower binding energy to O 2 , exhibited higher photocatalytic activity for oxidation of thioethers and coupling of benzylamines with excellent stability. The present work can serve as a reliable reference for the development of novel highly active and stable COF-based photocatalysts., (© 2024 Wiley-VCH GmbH.)

The syntheses of atomically precise silver (Ag) clusters stabilized by multidentate lacunary polyoxometalate (POM) ligands have been emerging as a promising but challenging research direction, the combination of redox-active POM ligands and silver clusters will render them unexpected geometric structures and catalytic properties. Herein, we report the successful construction of two structurally-new lacunary POM-stabilized Ag clusters, TBA 6 H 14 Ag 14 (DPPB) 4 (CH 3 CN) 9 [Ag 24 (Si 2 W 18 O 66 ) 3 ] ⋅ 10CH 3 CN ⋅ 9H 2 O ({Ag 24 (Si 2 W 18 O 66 ) 3 }, TBA=tetra-n-butylammonium, DPPB=1,4-Bis(diphenylphosphino)butane) and TBA 14 H 6 Ag 9 Na 2 (H 2 O) 9 [Ag 27 (Si 2 W 18 O 66 ) 3 ] ⋅ 8CH 3 CN ⋅ 10H 2 O ({Ag 27 (Si 2 W 18 O 66 ) 3 }), using a facile one-pot solvothermal approach. Under otherwise identical synthetic conditions, the molecular structures of two POM-stabilized Ag clusters could be readily tuned by the addition of different organic ligands. In both compounds, the central trefoil-propeller-shaped {Ag 24 } 14+ and {Ag 27 } 17+ clusters bearing 10 delocalized valence electrons are stabilized by three C-shaped {Si 2 W 18 O 66 } units. The femtosecond/nanosecond transient absorption spectroscopy revealed the rapid charge transfer between {Ag 24 } 14+ core and {Si 2 W 18 O 66 } ligands. Both compounds have been pioneeringly investigated as catalysts for photocatalytic CO 2 reduction to HCOOH with a high selectivity., (© 2023 Wiley-VCH GmbH.)

Pseudorabies virus (PRV) is the causative agent of Aujeszky's disease in pigs. The low-density lipoprotein receptor (LDLR) is a transcriptional target of the sterol-regulatory element-binding proteins (SREBPs) and participates in the uptake of LDL-derived cholesterol. However, the involvement of LDLR in PRV infection has not been well characterized. We observed an increased expression level of LDLR mRNA in PRV-infected 3D4/21, PK-15, HeLa, RAW264.7, and L929 cells. The LDLR protein level was also upregulated by PRV infection in PK-15 cells and in murine lung and brain. The treatment of cells with the SREBP inhibitor, fatostatin, or with SREBP2-specific small interfering RNA prevented the PRV-induced upregulation of LDLR expression as well as viral protein expression and progeny virus production. This suggested that PRV activated SREBPs to induce LDLR expression. Furthermore, interference in LDLR expression affected PRV proliferation, while LDLR overexpression promoted it. This indicated that LDLR was involved in PRV infection. The study also demonstrated that LDLR participated in PRV invasions. The overexpression of LDLR or inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9), which binds to LDLR and targets it for lysosomal degradation, significantly enhanced PRV attachment and entry. Mechanistically, LDLR interacted with PRV on the plasma membrane, and pretreatment of cells with LDLR antibodies was able to neutralize viral entry. An in vivo study indicated that the treatment of mice with the PCSK9 inhibitor SBC-115076 promoted PRV proliferation. The data from the study indicate that PRV hijacks LDLR for viral entry through the activation of SREBPs.IMPORTANCEPseudorabies virus (PRV) is a herpesvirus that primarily manifests as fever, pruritus, and encephalomyelitis in various domestic and wild animals. Owing to its lifelong latent infection characteristics, PRV outbreaks have led to significant financial setbacks in the global pig industry. There is evidence that PRV variant strains can infect humans, thereby crossing the species barrier. Therefore, gaining deeper insights into PRV pathogenesis and developing updated strategies to contain its spread are critical. This study posits that the low-density lipoprotein receptor (LDLR) could be a co-receptor for PRV infection. Hence, strategies targeting LDLR may provide a promising avenue for the development of effective PRV vaccines and therapeutic interventions., Competing Interests: The authors declare no conflict of interest.