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Catalytic technologies are pivotal in enhancing energy efficiency, promoting clean energy production, and reducing energy consumption in the chemical industry. The pursuit of novel catalysts for renewable energy is a long-term goal for researchers. In this work, we synthesized three two-dimensional covalent organic frameworks (COFs) featuring electron-rich carbazole-based architectures and evaluated their catalytic performance in photocatalytic organic reactions and electrocatalytic oxygen reduction reactions (ORRs). Pyrene-functionalized COF, termed as FCTD-TAPy, demonstrated excellent photocatalytic performance for amino oxidation coupling and showed a remarkable preference for substrates with electron-withdrawing groups (up to >99% Conv. and >99% Sel). Furthermore, FCTD-TAPy favored a four-electron transfer pathway during the ORR and exhibited favorable reaction kinetics (51.07 mV/dec) and a high turnover frequency (0.011 s−1). In contrast, the ORR of benzothiadiazole-based FCTD-TABT favored a two-electron transfer pathway, which exhibited a maximum double-layer capacitance of 14.26 mF cm−2, a Tafel slope of 53.01 mV/dec, and a hydrogen peroxide generation rate of 70.3 mmol g−1 h−1. This work underscores the potential of carbazole-based COFs as advanced catalytic materials and offers new insights into the design of metal-free COFs for enhanced catalytic performance.

Managing chronic non-healing wounds presents a significant clinical challenge due to their frequent bacterial infections. Mesoporous silica-based materials possess robust wound-healing capabilities attributed to their renowned antimicrobial properties. The current study details the advancement of mesoporous silicon-loaded MnO and CaO molecules (HMn-Ca) against bacterial infections and chronic non-healing wounds. HMn-Ca was synthesized by reducing manganese chloride and calcium chloride by urotropine solution with mesoporous silicon as the template, thereby transforming the manganese and calcium ions on the framework of mesoporous silicon. The developed HMn-Ca was investigated using scanning electron microscopy (SEM), transmission electron microscope (TEM), ultraviolet-visible (UV-visible), and visible spectrophotometry, followed by the determination of Zeta potential. The production of reactive oxygen species (ROS) was determined by using the 3,3,5,5-tetramethylbenzidine (TMB) oxidation reaction. The wound healing effectiveness of the synthesized HMn-Ca is evaluated in a bacterial-infected mouse model. The loading of MnO and CaO inside mesoporous silicon enhanced the generation of ROS and the capacity of bacterial capture, subsequently decomposing the bacterial membrane, leading to the puncturing of the bacterial membrane, followed by cellular demise. As a result, treatment with HMn-Ca could improve the healing of the bacterial-infected wound, illustrating a straightforward yet potent method for engineering nanozymes tailored for antibacterial therapy.

Owing to residual tumor tissues around the treatment margins, it is difficult to totally ablate large tumors, eliminate disseminated and metastatic nodules as well as prevent the tumor recurrence simultaneously by conventional photothermal therapy (PTT). In this work, PTT combined reactive oxygen species oxidative therapy (ROT) was conducted via mesoporous polydopamine nanosphere with nanoceria doping (MPDA-Ce). After surface anchoring with Arg-Gly-Asp (RGD) molecules, the dispersive stability and tumor targeting of this innovative nanoplatform were substantially boosted. In vitro studies revealed that the unique nanotherapeutics had satisfactory photothermal conversion efficiency (η = 51.41%), continuous nanoceria release in cytoplasm of tumor cells after acid microenvironment (pH = 5.5) induced biodegradation. Significantly, hyperthermia amplified the abundant reactive oxygen species generation under 808 nm laser irradiation that potent ROT was realized with only 27.1% cells alive. Strikingly, Indocyanine green (ICG) loaded MPDA-Ce with RGD modification shows robust tumor targeting capability in breast carcinoma bearing Balb/C mice under fluorescent imaging in the second near-infrared window. The combined treatments resulted in complete tumor cells eradication under 808 nm laser illumination both in vitro and in vivo. This work highlights the promising application of MPDA-Ce as a powerful nanoplatform for ROT and PTT combined treatment in clinical.

Four new unusual pentacyclic triterpenoids (1–4) were isolated from the roots of Jasminum sambac (L.) Ait. Their structures were elucidated by 1D and 2D NMR analysis, single-crystal X-ray diffraction and HRESIMS.

Li/CFx is one of the highest-energy-density primary batteries; however, poor rate capability hinders its practical applications in high-power devices. Here we report a preparation of fluorinated graphene (GFx) with superior performance through a direct gas fluorination method. We find that the so-called “semi-ionic” C-F bond content in all C-F bonds presents a more critical impact on rate performance of the GFx in comparison with sp2 C content in the GFx, morphology, structure, and specific surface area of the materials. The rate capability remains excellent before the semi-ionic C-F bond proportion in the GFx decreases. Thus, by optimizing semi-ionic C-F content in our GFx, we obtain the optimal x of 0.8, with which the GF0.8 exhibits a very high energy density of 1,073 Wh kg−1 and an excellent power density of 21,460 W kg−1 at a high current density of 10 A g−1. More importantly, our approach opens a new avenue to obtain fluorinated carbon with high energy densities without compromising high power densities.

A new nanostructural anion formulated as (H(sub 3)Mo(sub 57)V(sub 6)(NO)(sub 6)O(sub 189)-(H(sub 2)O)(sub 12)(VO)(sub 6)](super 15-) ({Mo(sub 57)V(sub 6)}) was obtained by chemically embellishing metal-oxygen fragments into the three outer cavities of the nanoanion [H(sub 3)Mo(sub 57)V(sub 6)O(sub 183)(H(sub 2)O)(sub 18)](super 21-) ({Mo-(sub 57)V(sub 6)}. The six embedded symmetry-related V2 centers have tetrahedral coordination environments and are verified as V(super v) ions via solid-state (super 51V NMR spectrum.

The photochemical transformations have gained widespread recognition in the recent years because of the generally mild reaction conditions needed for substrate activation, ideally the light alone and their appropriateness for green reactions. A variety of catalyst systems have been developed for visible light driven reactions. The unprecedented [Ru(bpy)3]2+ complexes as well as xanthene based organic dyes has gained widespread recognition due to their effectiveness and broad applications in organic synthesis. The Photoredox catalyst based on transition metal complexes or organic dyes have comparable redox abilities but each system has its own distinctive benefits. In this perspective photocatalytic efficacy of organometallic ruthenium and eosin Y have been investigated in connection to their pursuit for the photocatalytic oxidative coupling of N-aryl tetrahydroisoquinoline with carbon and sulfur containing nucleophiles. The eosin Y confirmed to be more efficient in our studies. The photophysical properties and reaction mechanism of both types of catalysts are well established in the literature. [ABSTRACT FROM AUTHOR]

Two interesting polyoxometalate-templated host-guest compounds 1 and 2 with the same chemical formulae of [Ag6(tpt)4(SiW12O40)Cl2]·2H2O have been obtained by hydrothermal reactions of monolacunary Keggin-type K8[a-SiW11O39]·13H2O with CH3COOAg and tpt ligands under different pH conditions. Compounds 1 and 2 are structural isomers. In 1, the novel chair-like tetranuclear [Ag4(µ3-Cl)2]2+ clusters and additional Ag+ ions are linked by tpt ligands to form a 2D double-layered structure featured with two different types of voids in the layer, and the double-layers are stacked into a 3D host supramolecular framework with 1D channels filled with Keggin [SiW12O40]4- polyoxoanions and water molecules as guests. In 2, Ag+ ions are linked by tpt ligands into a 3D framework of 10³-ths topology. The most outstanding structural feature of 2 is that upon six-fold interpenetration among 10³-ths nets there are still nanosized channels along the a axis to accommodate Keggin polyoxoanions and water molecules as guests. Compound 2 represents the first example of six-fold interpenetrating cationic networks templated with polyoxoanions. In this work, the obvious differences in structure between 1 and 2 show that hydrochloric acid solution conditions, which offer not only H+ to regulate the pH value but also Cl- to coordinate with Ag+ ions, play an important role in the formation of host frameworks templated by Keggin-type polyoxoanions. The photoluminescence properties of 1 and 2 have been investigated in the solid state. [ABSTRACT FROM AUTHOR]

A novel three-dimensional metal-organic framework (MOF), Ag4(tpt)4{δ-[Mo8O26]}.1.5H2O (A) (tpt = 2,4,6-tris(4-pyridyl)-1,3,5-triazine), possesses a ths-type topology with the hinge deformation mode. The single-crystal X-ray diffraction study shows that A and the dehydrated phase Ag4(tpt)4{δ-[Mo8O26]} (B) display distinct anisotropic thermal expansion with expansion in the b direction but contraction in the ac plane. This rare area negative thermal expansion (NTE) behavior is attributed to the hinged structure model and the supramolecular interactions (argentophilic interaction, π-π interaction) that act as the microscopic driving forces. In addition, supramolecular interactions also play a key role in thermochromic behavior of compound A. [ABSTRACT FROM AUTHOR]

Luminescent heteroleptic CuIcomplexes based on asymmetrical iminephosphine ligands exhibit improved electrochemical and photochemical stability as compared to the analogous complexes based on traditional diimine or diphosphine ligands. [ABSTRACT FROM AUTHOR]

At room temperature, a new coordination polymer [Ni(tpt)(imi)3(H2O)]n was synthesized by the reaction of NiCl2⋅6H2O, terephthalic acid, and imidazole in aqueous solution. The structure was determined by X-ray crystallography. It crystallizes in monoclinicP21/n space group with the crystal cell parameters ofa = 9.8626(4) Å,b = 15.2498(3) Å, andc = 12.7681(3)Å, β = 90.309(2)∘,V = 1920.33(10) Å3, andZ = 4. The crystal X-ray analysis shows that each nickel atom is coordinated by three imidazole ligands, two terephthalate ions, and one water molecule. Each terephthalate ion bridges two nickel atoms to form a zigzag chain. The chains are further linked together via hydrogen bonds to a three-dimensional network. [ABSTRACT FROM AUTHOR]

The monomeric lead(II) complex, [Pb(phen)(H2O)(NO3)2] was prepared by a hydrothermal reaction of Pb(NO3)2, nitrilotriacetic acid, NaOH, 1,10-phenanthroline, and H2O. The structure was determined by X-ray crystallography. It crystallizes in monoclinic P2(1)/n space group with the crystal cell parameters of a = 6.3568(6), b = 20.2345(19), c = 11.2722(9) Å, β = 98.337(4)∘, V = 1434.6(2) Å3, and Z = 4. The crystal X-ray analysis shows that the lead atom is six-coordinated by two N atoms of phen ligand, three oxygen atoms of nitrate anions and one water molecule. Owing to the presence of a lone pair of electrons of lead atom, a significant gap occurs in the coordination geometry around Pb ion. A 3D architecture is formed through the strong hydrogen bonding and π–π stacking interactions. [ABSTRACT FROM AUTHOR]

A new member of giant polyoxomolybdate containing bridging hydroxylamine groups has been unexpectedly obtained during the preparation of the material of {Mo57V6}, (NH4)4Na2[Mo36VIO108(NH2OH)2(OH))6(H2O)12] · 35H2O. The title compound crystallizes in the monoclinic space group P2(1)/n, a= 16.7886(2), b = 18.4309(3), c = 24.49950(10) Å, β = 99.58°, V = 7475.18(15) ų, Z = 2, and Dcalc = 2.817. Each giant cluster anion [Mo36VIO108(NH2OH)2(OH)6 (H2O)12]6- ({Mo36(NO)2}) consists of two large [Mo15VIO50(MoO24+(µ-NH2(OH) (µ-OH)(t-OH)2(t-OH2)6]5- ({Mo17} units linked together by two {MoO2}2+ centers; these anions {Mo36(NO)2} are further connected via distorted monocapped pentagonal-pyramidal sodium into a three-dimensional structure with channels that filled with lattic water molecules and NH4+ ions. KEY WORDS: Giant polyoxomolybdate; synthesis and crystal structures; bridging hydroxylamine groups. [ABSTRACT FROM AUTHOR]

The novel tubular framework of [(V[sup IV]O)[sub 3](µ[sub 4]-PO[sub 4])[sub 2](2,2'-bpy)(µ-OH[sub 2])]· 1/3H[sub 2]O, which was synthesized from hydrothermal reaction, possesses some attractive structural features: (i) O=V[sup IV]O[sub 4](OH[sub 2]) octahedra and P0[sub 4] tetrahedra linked together by corner-sharing and face-sharing into a cylinder-shaped channel including 6 water molecules per cell unit, and (ii) (VO)(2,2'-bpy) groups regularly arranged around the tube, so that the 2,2-bpy ligands constitute an organic shell around an aqueous polar channel. [ABSTRACT FROM AUTHOR]

The heteropoly compound [(V[sup V]O[sub 4])Mo[sup Vl][sub 12]O[sub 36](V[sup lV]O)[sub 6]][(OH)[sub 9]]. ·11 H[sub 2]O (1), synthesized by hydrothermal method under weak basic conditions, represents the first mixed MoN six-capped Keggin structural derivative with a spherical skeleton, and the first transition metal polyoxocation. The successful synthesis of 1 demonstrates that basic hydrothermal synthesis might be a power synthetic route to the isolation of more new polycationic metal-oxo clusters. [ABSTRACT FROM AUTHOR]

Focuses on the synthesis of polyoxomolybdate by reducing an acidified aqueous solution. Accommodation of five edge-shared sodium cations; Construction of the polyoxomolybdate structure by a 46-member crown-shaped anion; Crystal data of compound polyoxomolybdate.