Carbon capture and hydrocarbon purification via economically viable and energy-efficient membrane systems have recently attracted increased interest. Mixed matrix membranes (MMMs) made from metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), and 2-dimensional (2D) materials such as MXenes and layered double hydroxides (LDHs) are particularly attractive for gas separations. This work conducted a critical review of the latest development of MMMs based on advanced filler functionalization strategies, and their performances and stabilities under different operating conditions related to pressure, temperature, and feed gas impurities. Moreover, the upscaling and techno-economic feasibility of MMMs for industrial applications in postcombustion carbon capture, natural gas sweetening, biogas upgrading, hydrogen purification and olefin/paraffin separation were systematically discussed. Advanced MMMs developed at higher technology readiness levels are still challenging to meet their industrial gas separations. Herein, we present the latest ideas for improving fillers for MMMs and optimizing process design with regard to enhancing material properties and process efficiency. These concepts are expected to be implemented in next-generation MMMs to achieve high separation performance.

Combined molecular, physicochemical and chemical properties of electrophilic warheads can be applied to create covalent drugs with diverse facets. Here we study these properties in fluorinated diketones (FDKs) and their multicomponent equilibrium systems in the presence of protic nucleophiles, revealing the potential of the CF₂(CO)₂ group to act as a multifaceted warhead for reversible covalent drugs. The equilibria compositions of various FDKs in water/octanol contain up to nine species. A simultaneous direct species-specific ¹⁹F-NMR-based log P determination of these complex equilibria systems was achieved and revealed in some cases lipophilic to hydrophilic shifts, indicating possible adaptation to different environments. This was also demonstrated in ¹⁹F-MAS-NMR-based water-membrane partitioning measurements. An interpretation of the results is suggested by the aid of a DFT study and ¹⁹F-DOSY-NMR spectroscopy. In dilute solutions, a model FDK reacted with protected cysteine to form two hemi-thioketal regioisomers, indicating possible flexible regio-reactivity of CF₂(CO)₂ warheads toward cysteine residues.

Nanometer-scaled objects are known to have dimension-related properties, but sometimes the assembly of such objects can lead to the emergence of other properties. Here, we show the assembly of atomically precise gold nanoclusters into large fibrillar structures that are featuring excitation-dependent luminescence with an excitation-selective circularly polarized luminescence (CPL), even though all components are achiral. The origin of CPL in the assembly of atomic clusters has been attributed to the hierarchical organization of atomic clusters into fibrillar structures, mediated via a hydrogen bonding interaction with a surfactant. We follow the assembly process both experimentally and computationally showing the advance in the structural formation along with its chiroptical electronic properties, i.e., circular dichroism (CD) and CPL. Our study here can assist in the rational design of materials featuring chiroptical properties, thus leading to a controlled CPL activity.

Vibrational strong coupling results from the interaction between optically allowed molecular vibrational excitations and the resonant mode of an infrared cavity. Strong coupling leads to the formation of hybrid states, known as vibrational polaritons, which are readily observed in transmission measurements and a manifold of the reservoir states. In contrast, Raman spectroscopy of vibrational polaritons is elusive and has recently been the focus of both theoretical and experimental investigations. Because Raman measurements are frequently performed with high-numerical aperture excitation/collection optics, the angular dispersion of the strongly coupled system must be carefully considered. Herein, we experimentally investigated vibrational polaritons involving dispersive collective lattice resonances of infrared antenna arrays. Despite clear indications of the strong coupling to vibrational excitations in the transmission spectrum; we found that Raman spectra do not bear signatures of the polaritonic transitions. Detailed measurements indicate that the disappearance of the Raman signal is not due to the polariton dispersion in our samples. On the other hand, the Tavis–Cummings–Holstein model that we employed to interpret our results suggests that the ratio of the Raman transition strengths between the reservoir and the polariton states scales according to the number of strongly coupled molecules. Because the vibrational transitions are relatively weak, the number of molecules required to achieve strong coupling conditions is about 10⁹ per unit cell of the array of infrared antennas. Therefore, the scaling predicted by the Tavis–Cummings–Holstein model can explain the absence of the polariton signatures in spontaneous Raman scattering experiments.

The tetrasilyl-substituted distannene, (tBu2HSi)2Sn=Sn(SiHtBu2)2 6, was synthesized by mild thermolysis (70°C in hexane) of tris(di-tert-butyl-hydridosilyl)stannane 4. The X-ray crystallography structure of 6 reveals the following unusual structural properties: a planar geometry around both Sn atoms (Σ∡Sn = 359.87°), a non-twisted Sn=Sn double bond, and the shortest Sn=Sn double bond of 2.599 Å among all acyclic distannenes. Thus, compound 6 is the first reported distannene having a structure closely analogous to a classic alkene. Reactions of 6 with CCl4 or with 2,3-dimethylbuta-1,3-diene to produce 1,2-dichlorodistannane 9 and the [2+4] cycloadduct 10, respectively, are characteristic for a Sn=Sn double bond.

The Annual Wolf Prize Symposia of the Israel Chemical Society (ICS) have become a significant component of the scientific landscape of the State of Israel. These highly attended events occur annually in late May or early June as part of the Wolf Prize week, usually one day before the award ceremony in the Knesset. This account covers the one-day symposium at the Weizmann Institute of Science on June 14, 2023, the Wolf Prize ceremony in the Knesset on June 15, and several other events in Israel that week, all honoring Chuan He, Jeffrey W. Kelly, and Hiroaki Suga.

Hydrogel based on hydrophilic, crosslinked networks can reduce surface contamination in aqueous environment due to their low adhesion, biocompatibility and tunable properties. In particular, sub-micron hydrogel films can potentially screen a surface from interaction with foulant colloids and microorganisms without compromising original functions, such as water permeation in membranes. This study focuses on preparation and understanding of the adhesive and micromechanical properties of thin hydrogel films and factors affecting the dynamics of microparticle deposition on such films, mimicking the initial stages of surface fouling with colloids, microparticles and microorganisms. For this purpose, a simple procedure was developed to simultaneously prepare, crosslink and covalently anchor multi-arm-PEG precursors to a surface to form a submicron coating as a representative model. The effects of synthetic parameters and external conditions on adhesion and viscoelasticity were studied by force spectroscopy using polystyrene colloidal probes. The same particles were also employed in macroscopic deposition experiments in a parallel plate flow cell under identical solution conditions. Microscopic adhesion and elasticity were unaffected by the hydrogel crosslinking density and by salinity, but strongly affected by solution pH and dwell time, whereas macroscopic deposition was strongly affected both by salinity and by pH. These differences were ascribed to the effect of long-range doule-layer forces, involved in deposition but absent in measurements of adhesion and elasticity. The results highlight the differences and similarities between the two types of measurements and underlying phenomena, as a step towards understanding and rational design of soft antifouling coatings.

Considering the worldwide efforts for designing catalysts that are not based on platinum group metals while still reserving the many advantages thereof, this study focused on the many variables that dictate the performance of cathodes used for fuel cells, regarding the efficient and selective reduction of oxygen to water. This was done by investigating two kinds of porous carbon electrodes, modified by molecular cobalt(III) complexes chelated by corroles that differ very much in size and electron-withdrawing capability. Examination of the electronic effect uncovered shifts in the Co^II/Co^III redox potentials and also large differences in the affinity of the cobalt center to external ligands. Spontaneous absorption of the catalysts was found to depend on the size of the corrole’s substituents (C₆F₅ ≫ CF₃ ≫ H) and the metal’s axial ligands (PPh₃ versus pyridine), as well as on the porosity of the carbon electrodes (BP2000 > Vulcan). The better-performing cobalt-based catalysts were almost as active and selective as 20% platinum on Vulcan in terms of the onset potential and the only 2–10% undesirable formation of hydrogen peroxide. Durability was also addressed by using the best-performing modified cathode in a proper anion-exchange membrane fuel cell setup, revealing very little voltage change during 12 h of operation.

Solvodynamic shear describes the shear stresses produced by the movement of solvent molecules over slower-moving objects, such as a surface or macromolecules. This phenomenon is commonly attributed in the literature to driving solution polymer mechanochemistry — the scission of chemical bonds (even very strong ones) in covalent macromolecules¹. Polymer mechanochemistry via solvodynamic shear has found significant interest in the scientific community and is also relevant in various polymer solution applications. When large amounts of oil and water are moved in pipes, high-molecular-weight (M_w) polymers (called drag-reducing agents) are added to reduce the liquid turbidity and obtain a laminar flow, reducing the energy expenditure in pumps². Motor oil and lubricants undergo significant shear, and they include numerous polymer additives to maintain the oil viscosity at high temperatures or to inhibit oil freezing³.

Targeting the cell nucleus remains a challenge for drug delivery. Here, we present a universal platform for the smart design of nanoparticle (NP) decoration that is based on: (i) a spacer polymer, commonly biotin-polyethylene-glycol-thiol, whose grafting density and molecular weight can be tuned for optimized performance, and (ii) protein binding peptides, such as cell penetrating peptides (CPPs), cancer-targeting peptides, or nuclear localization signal (NLS) peptides, that are linked to the PEG free-end by universal chemistry. We manifested our platform with two different bromo-acetamide (Br-Ac) modified NLSs. We used cell extract-based and live cell assays to demonstrate the recruitment of dynein motor proteins, which drive the NP active transport toward the nucleus, and the enhancement of cellular and nuclear entry, manifesting the properties of NLS as a CPP. Our control of the NP decoration scheme, and the modularity of our platform, carry great advantages for nano-carrier design for drug delivery applications.