Dalton Transactions最新文献

Integrated compositional and morphological designs provide an effective strategy to optimize both thermodynamic and kinetic behaviors, thus enabling the construction of high-efficiency electrocatalysts. Herein, we develop ReS₂ and FeS₂ heterojunction nanosheet arrays arranged on a carbon cloth substrate (labeled as ReS₂/FeS₂@CC hereafter) through a one-step hydrothermal strategy. Experimental data demonstrated that the construction of heterojunctions and sheet-like arrays can freely reconfigure the electronic configuration, expedite charge transfer, and provide abundant reactive sites. Consequently, the ReS₂/FeS₂@CC electrode exhibits outstanding hydrogen evolution performance in an alkaline medium, with an overpotential of 109 mV, affording a current density of 10 mA cm^-2, a Tafel slope of 103.7 mV dec^-1 and long-term electrochemical stability in the i-t test for 56 h and the 4000-cycle test, thereby offering a promising method for sustainable and economical H₂ production.

Boron-substituted silyllithium was synthesized via Sn-Li exchange between the corresponding (boryl)silylstannane and n-BuLi and reacted with chlorosilanes to afford a series of Si-B-containing di-, tri-, and tetrasilanes. The tri- and tetrasilane derivatives were examined by UV-vis spectroscopy and density functional theory calculations to assess the electronic consequences of boron incorporation into σ-conjugated silane frameworks. In addition, the diaminoboryl moiety bound to boron can be selectively transformed into a pinacolatoboryl group without Si-B bond cleavage. Overall, this work provides a chemically intuitive entry to Si-B-containing oligosilanes and enables systematic investigation of boron incorporation into σ-conjugated silane frameworks.

Intermetallic palladium-based nanomaterials hold great promise for alcohol electrooxidation, but the role of surface topography in governing interfacial catalytic processes remains underexplored. Herein, we report a comparative investigation of intermetallic Pd₃Pb nanosheets with flat and crumpled surface topographies, where the crumpled morphology is achieved by introducing N-(octadec-9-en-1-yl)diethanolamine during synthesis, while flat nanosheets are obtained in its absence. For ethanol oxidation, the crumpled Pd₃Pb nanosheets deliver a mass activity of 1742.9 mA mg^-1 and retain 10.0 mA cm^-2 after 100 cycles, substantially outperforming flat nanosheets (1192.8 mA mg^-1, 3.4 mA cm^-2) and commercial Pd/C (709.2 mA mg^-1, 1.1 mA cm^-2). In situ Raman spectroscopy reveals that the reaction proceeds predominantly via the C1 pathway, evidencing efficient C-C bond cleavage on the crumpled surface. By using density functional theory simulations this enhancement can be attributed to localized surface strain induced by the crumpled topography-modeled on the Pd₃Pb(311) surface-which upshifts the d-band center to -1.53 eV and strengthens *OH binding (-3.29 eV), thereby optimizing intermediate adsorption energetics and facilitating the oxidative removal of carbonaceous poisons. This work provides a synthetic route to engineer crumpled surface topography in intermetallic nanosheets and demonstrates its critical role in regulating interfacial catalysis for C1-selective alcohol electrooxidation.

Zero-dimensional organic-inorganic hybrid metal halides have emerged as promising luminescent materials with structural diversity and tunable emission properties. However, it remains challenging to precisely control the metal coordination environment to suppress non-radiative recombination and improve the photoluminescence quantum yield (PLQY). Herein, we report an acid-solvent synergistic strategy that enables stepwise evolution of Sb coordination environments in hybrid halides. The non-emissive phase (H₂PIP)[SbCl₅]·H₂O (1, PIP = piperazine), composed of edge-sharing [Sb₂Cl₁₀]^4- dimers, transforms into an orange-emitting intermediate (H₂PIP)₅(H₅O₂)[SbCl₅]₂[SbCl₆]Cl₄ (2) with mixed discrete polyhedra, in the presence of HCl. Upon CH₃CN incorporation, the mixed Sb coordination polyhedra transform into isolated [SbCl₆]^3- octahedra in green-emitting compound (H₂PIP)₂(NH₄)[SbCl₆]Cl₂·CH₃CN (3). Accompanying this evolution of coordination environments, the PLQY rises from <1% to 23.6% for the intermediate and ultimately reaches 90.4%. The enhanced PLQY originates from the expanded Sb⋯Sb distance and significant [SbCl₆]^3- octahedral distortion, which facilitate the formation and radiative recombination of self-trapped excitons. This work provides insights into acid-solvent directed coordination engineering for highly efficient Sb-based hybrid emitters.

A new heteroleptic luminescent and photocytotoxic ruthenium(II) polypyridyl complex, [Ru^II(bphen)₂(cur)]⁺ (bphen = bathophenanthroline, cur = curcumin), has been thoroughly investigated for its photophysical properties with potential as a luminescent probe for bioimaging and a photocytotoxic agent. The optimized lead complex was obtained via coordinating curcumin to the Ru(II) center pre-coordinated with two bathophenanthroline ligands, producing a stable cationic structure with extended π-conjugation. The incorporation of curcumin to {Ru(bphen)₂} moiety improves emissive characteristics and also enhances the biological compatibility, owing to its natural origin and functional groups that interact with biomolecular environments. The complex exhibits good photostability and strong emission under physiological conditions, enabling its application as a luminescent stain for fluorescence-based cellular imaging. Furthermore, in vitro photocytotoxicity studies in the human breast cancer cell line MCF-7 reveal a significant photocytotoxicity index (PI ∼ 19.5), indicating low dark toxicity but an enhanced cytotoxic response upon visible-light irradiation. These findings highlight the dual functionality of the [Ru^II(bphen)₂(cur)]⁺ as a theragnostic agent, serving as a luminescent bioimaging probe and a potential photosensitizing agent for light-activated therapeutic applications.

2-Methyl benzoselenazoles were synthesized via the reaction of in situ-generated sodium selenolate with acetyl chloride at room temperature. Single-crystal X-ray diffraction confirmed a nearly planar structure due to non-bonding Se⋯O interactions, supported by computational analyses. All compounds exhibited good glutathione peroxidase-like antioxidant activity in a coupled reductase assay, as compared to the reference, ebselen. The most active compound was further evaluated under varying concentrations of glutathione to gain deeper insights into its catalytic efficiency. ⁷⁷Se{¹H} NMR mechanistic study was performed to provide evidence for the key intermediates involved in the decomposition of peroxide. The radical-trapping antioxidant activity of benzoselenazoles was evaluated by the inhibition of azo-initiated autoxidation of cumene in chlorobenzene. It showed peroxyl radical-trapping capability, with an inhibition constant of 1.4 × 10³ M^-1 s^-1 and a stoichiometric factor (n) ≈ 2, due to H-atom transfer from the amide group, as further confirmed by theoretical calculations. In addition to their antioxidant activities, molecular dynamics studies revealed favourable binding interactions with vascular endothelial growth factor receptor-2 (VEGFR-2), suggesting dual antioxidant and anti-angiogenic roles.