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The adsorption behavior of gold thiosulfate ions on the surface of kaolinite was studied using a combination of experimental research and quantum chemical calculations. Under the condition of a stirring time of 30 min, a stirring speed of 500 r·min−1, and a mass ratio of 30% kaolinite in the slurry, when the initial gold concentration of 56.50 mg·L−1,the adsorption rate of gold-thiosulfate ions from a kaolinite-containing solution was 7.44%. The results of Fourier transform infrared spectroscopy (FTIR) and energy dispersive spectroscopy (EDS) showed that the physical and chemical adsorption of kaolinite and gold thiosulfate occurred in solution. Quantum chemical calculations were performed using the CASTEP module in Materials Studio. The adsorption energy of gold thiosulfate on the surface of kaolinite (001) was calculated as − 438.01 kJ·mol−1.The calculated H76–O289 distance was 1.615 Å. Mulliken Charge population analysis and bond population analysis showed that gold thiosulfate ions form relatively stable bonds on the kaolinite surface (001). In the process of thiosulfate immersion, part of gold is adsorbed by kaolinite, which affects the extraction of gold. These results indicate that during the leaching process of gold thiosulfate, kaolinite has the ability to "catch" gold, which affects the leaching efficiency. [ABSTRACT FROM AUTHOR]

A zinc supracluster [Zn24(ATZ)18(AcO)30(H2O)1.5]·(H2O)3.5 (Zn24), and a 1D zinc supracluster chain {[Zn24(ATZ)18(AcO)30(C2H5OH)2(H2O)3]·(H2O)2.5}n (1-D⊂Zn24) with molecular diameters of 2 nm were synthesized under regulatory solvothermal conditions or the micro bottle method. In an N,N-dimethylformamide solution of Zn24, Fe3+, Ni2+, Cu2+, Cr2+ and Co2+ ions exhibited fluorescence-quenching effects, while the rare earth ions Ce3+, Dy3+, Er3+, Eu3+, Gd3+, Ho3+, La3+, Nd3+, Sm3+, and Tb3+showed no obvious fluorescence quenching. In ethanol solution, the Zn24 supracluster can be used to selectively detect Ce3+ ions with excellent efficiency (limit of detection (LOD) = 8.51 × 10−7 mol/L). The Zn24 supracluster can also detect wavelengths between 302 and 332 nm using the intensity of the emitted light. [ABSTRACT FROM AUTHOR]

Metal‐complex‐based materials for lithium storage have attracted great interest due to their highly designable structures with multiple active sites and well‐defined lithium transport pathways. Their cycling and rate performances, however, are still constrained by structural stability and electrical conductivity. Herein, we present two hydrogen‐bonded complex‐based frameworks with excellent lithium storage capability. Multiple hydrogen bonds among the mononuclear molecules result in three‐dimensional frameworks that are stable in electrolyte. The origin of the remarkable lithium storage performance of this family was revealed through kinetic analysis and DFT calculations. [ABSTRACT FROM AUTHOR]

Front Cover: Hydrogen-bonded Complex-based Frameworks for Stable Lithium Storage (Chem. Lithium-ion battery, Metal-organic complex, Hydrogen-bonded framework, Dimensional design Keywords: Lithium-ion battery; Metal-organic complex; Hydrogen-bonded framework; Dimensional design EN Lithium-ion battery Metal-organic complex Hydrogen-bonded framework Dimensional design 1 1 1 07/05/23 20230703 NES 230703 B Hydrogen-bonded complex-based frameworks b were applied for the development of high-performance anode materials of lithium-ion batteries. [Extracted from the article]

The local charge distribution of photocatalyst is crucial to the catalytic activity due to its influence on the charge separation process. Herein, we report two one-dimensional Ni-based metal-organic assemblies for efficient photocatalytic hydrogen evolution without using noble-metal cocatalysts. By adjusting the aromatic ring in the center of the tricarboxylic ligand, the photocatalytic hydrogen evolution activity was increased from 1715 to 2652 μmol h-1 g-1. The detailed mechanism study shows that the introduced nitrogen atoms in the ligands of the metal-organic coordination assembly could modulate the local charge distribution, and yielding a significant enhancement of the molecular dipole moment which engenders a propulsive force for the effective separation and transport of photoinduced charge carriers. This work provides insights into the local charge distribution via ligand modulation for enhancing the activity of photocatalysts., (© 2024 Wiley‐VCH GmbH.)

Persistent organic pollutants (POPs) exist widely in the environment and place significant impact on human health by bioaccumulation. Efficient recognition of POPs and their removal are highly challenging tasks because their specific structures interact often very weakly with the capture materials. Herein, a molecular nanocage ( 1 ) is studied as an efficient sensing and sorbent material for POPs, which is demonstrated by a representative and stable perfluorooctane sulfonate (PFOS) substrate containing a hydrophilic sulfonic group and a hydrophobic fluoroalkyl chain. A highly sensitive and unusual turn-on fluorescence response within 10 s and a 97% total removal of PFOS from water in 20 min have been achieved owing to the strong host-guest interactions between 1 and PFOS. The binding constant of 1 to PFOS is 2 orders of magnitude higher than state-of-the-art adsorbents for PFOS and thus represents a new benchmark material for the recognition and removal of PFOS. The host-guest interaction has been elucidated by solid-state NMR spectroscopy and single-crystal X-ray diffraction, which provide key insights at a molecular level for the design of new advanced sensing/sorbent materials for POPs.

Entacapone (ENT) is a powerful catechol-O-methyl transferase inhibitor that is used for the diagnosis and treatment of Parkinson's syndrome, but the amount used must be well controlled to avoid overtreatment and side effect. Fast and selective detection of ENT needs well-matched energy levels and well-designed sensor-ENT interaction which is highly challenging. In this work, a water stable europium-based metal-organic framework (Eu-TDA) was synthesized to detect ENT by luminescence with excellent reusability and selectivity in the presence of main coexisting and interference species of plasma with a limit of detection of 5.01 μM. The experimental results showed that the luminescence of Eu-TDA can be effectively quenched by ENT via well-designed photoinduced electron transfer mechanism and internal filtration effect mechanism in the system., (© 2021 Wiley-VCH GmbH.)