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Artificial ionic sensory systems, bridging the divide between biological systems and electronics, mimic human skin functions but face critical challenges with biocompatibility, comfort, signal stability, and simplifying packaging. Here, we present a simple and permeable skin-interfaced iontronic mechanosensing (SIIM) architecture that integrates human skin as natural ionic material and hierarchically porous MXene-fiber composite membranes as sensing electrodes. The SIIM system eliminates complex ionic material design and multilayer matrix, exhibiting ultrahigh pressure sensitivities (5.4 kPa–1, <75 Pa), a low detection limit (6 Pa), excellent output stability along with high permeability to minimize the impact of sweating on sensing. The noncytotoxic nature of SIIM electrodes ensures excellent biocompatibility (>97% cell coincubational viability), facilitating long-term wearability and high biosafety. Furthermore, the scalable SIIM configuration integrated with matrix smart gloves, effectively monitors human physical movements. This SIIM-based sensor with marked sensing capabilities, structural simplicity, and scalability, holds promising potential in diverse wearable applications.

Nitrogen fixation is a complex process involving the transfer of six electrons and protons. Diverging from the conventional Haber-Bosch process, which relies on hydrogen (H2) to provide both electrons and protons to reduce nitrogen (N2), homogeneous transition metal complex-catalyzed N2reduction reactions (NRR) employ an array of electron and proton donors or even electron donors combined with silanes. As the synthesis of diverse catalytic progress, the categories of donors have seen rapid expansion. However, existing literature only provides summaries regarding the metal, ligands, and mechanism. Despite the significance of electron and proton donor combinations in nitrogen reduction reactions, no literature has thoroughly reviewed this aspect. Therefore, we hereby compiled a comprehensive list of commonly used reagents in N2reduction and classified them according to their specific donor combinations. This review presents clear and organized information about these combinations, along with a summary of their general performance trend in NRR with related catalysts. Finally, we conclude the discussion by highlighting key points for researchers to consider when selecting catalysts and donor combinations, with the ultimate goal of advancing the field of nitrogen fixation.

Copper selenide (Cu–Se) and copper sulfide (Cu–S) are promising cathodes for magnesium-ion batteries. However, the low electronic conductivity of Cu–Se system results in a poor rate capability and unsatisfactory cycling performance. Mg-ion batteries based on the Cu–S cathode exhibited large kinetic barriers during the recharging process owing to the presence of polysulfide species. This work attempts to circumvent this dilemma by doping Cu1.8Se by sulfur, which replaces the selenium in the CuSe lattice to form Cu1.8Se0.6S0.4nanocrystalline powder. The presence of sulfur will increase the electronic conductivity, and the presence of selenium will mitigate the effect of polysulfide species that hinder the kinetics of Mg2+. Herein, a Cu1.8Se0.6S0.4nanocrystalline powder was synthesized by the solid-state reaction, yielding a highly pure and stoichiometric powder. The crystallographic structure of the nanopowder and the conversion-type storage mechanism have been attested via ex situ X-ray diffraction and energy-dispersive X-ray analysis. The nanocrystalline feature of Cu1.8Se0.6S0.4was demonstrated by high-resolution transmission electron microscopy. An apparent surface morphology change during the charging/discharging process has been visualized by a field emission scanning electron microscope. Diffuse reflectance spectroscopy has discussed the variation of the band gap during charging and discharging. The full Mg/Cu1.8Se0.6S0.4cells presented an initial discharge capacity of 387.99 mAh g–1at a current density of 0.02 mA cm–2; moreover, they show moderate diffusion kinetics with DMg2+≈ 10–15cm–2s–1.

Growing continuous monolayer films of transition-metal dichalcogenides (TMDs) without the disruption of grain boundaries is essential to realize the full potential of these materials for future electronics and optoelectronics, but it remains a formidable challenge. It is generally believed that controlling the TMDs orientations on epitaxial substrates stems from matching the atomic registry, symmetry, and penetrable van der Waals forces. Interfacial reconstruction within the exceedingly narrow substrate-epilayer gap has been anticipated. However, its role in the growth mechanism has not been intensively investigated. Here, we report the experimental conformation of an interfacial reconstructed (IR) layer within the substrate-epilayer gap. Such an IR layer profoundly impacts the orientations of nucleating TMDs domains and, thus, affects the materials’ properties. These findings provide deeper insights into the buried interface that could have profound implications for the development of TMD-based electronics and optoelectronics.

A novel α,β-regioselective [3+2] cycloaddition reaction of arylallene with C,N-cyclic azomethine imine is reported. The axial-to-central chirality transfer phenomenon has been disclosed with chiral allenes in the reaction. The wide substrate scope, including different functional groups and natural products, reveals the generality of the methodology. Both experiments and density functional theory calculations have been used to elucidate a plausible mechanism.

In this work, we fabricated a highly efficient and reabsorption-free transparent X-ray imaging scintillator with high performance using an efficient triplet-triplet energy transfer strategy between thermally activated delayed fluorophore (TADF-Br) and iridium organometallic complex (Ir-OMC). Steady-state and ultrafast time-resolved experiments—supported by high-level density functional theory calculations—clearly demonstrate that efficient triplet-triplet energy transfer from TADF-Br with a high X-ray absorption cross-section to emissive Ir-OMC can be achieved. Such high efficiency of interfacial triplet energy transfer and the heavy atoms in both the donor and acceptor led to a remarkable enhancement in triplet-state radioluminescence upon X-ray irradiation. The fabricated X-ray imaging scintillator achieved an X-ray imaging resolution of 19.8 lp mm−1, exceeding the resolution of most reported organic and organometallic scintillation screens.

Crystallographic characterization of RuX(CO)(η3-C3H5)(JOSIPHOS), where X = Cl, Br, or I, reveals a halide-dependent diastereomeric preference that defines metal-centered stereogenicity and, therefrom, the enantioselectivity of C−C coupling in ruthenium-catalyzed anti-diastereo- and enantioselective C−C couplings of primary alcohols with 1-aryl-1-propynes to form products of carbonyl anti-(α-aryl)allylation. Computational studies reveal that a non-classical hydrogen bond between iodide and the aldehyde formyl CH bond stabilizes the favored transition state for carbonyl addition. An improved catalytic system enabling previously unattainable transformations was developed that employs an iodide-containing precatalyst, RuI(CO)3(η3-C3H5), in combination with trifluoroethanol, as illustrated by the first enantioselective ruthenium-catalyzed C−C couplings of ethanol to form higher alcohols.

Water oxidation is a primary step in natural as well as artificial photosynthesis to convert renewable solar energy into chemical energy/fuels. Electrocatalytic water oxidation to evolve O2, utilizing suitable low-cost catalysts and renewable electricity, is of fundamental importance considering contemporary energy and environmental issues, yet it is kinetically challenging owing to the complex multiproton/electron transfer processes. Herein, we report the first cobalt-based pincer catalyst for catalytic water oxidation at neutral pH with high efficiency under electrochemical conditions. Most importantly, ligand (pseudo)aromaticity is identified to play an important role during electrocatalysis. A significant potential jump (∼300 mV) was achieved toward a lower positive value when the aromatized cobalt complex was transformed into a (pseudo)dearomatized cobalt species. The dearomatized species catalyzes the water oxidation reaction to evolve oxygen at a much lower overpotential (∼340 mV) on the basis of the onset potential (at a current density of 0.5 mA/cm2) of catalysis at pH 10.5, outperforming other Co-based molecular catalysts reported to date. These observations may provide a new strategy for the judicious design of earth-abundant transition-metal-based water oxidation catalysts.

We present the mechanistic understanding of an electrochemically-driven nickel-catalyzed coupling reaction. Computational analysis reveals that the spin density is mostly residing on the nickel (Ni) center when NiIIis reduced to NiI. Ni-mediated halogen atom abstraction through outer-sphere electron-transfer pathway to yield coupling products under mild conditions is demonstrated. Importantly, we have elucidated the role of NiIand Ni0for successive coupling of benzyl bromide and benzyl chloride derivatives, respectively, to corresponding bibenzyl products. The Ni-catalyst bearing a PN3P-ligand is an effective catalyst, producing a strong ligand effect on the reactivity and selectivity for the homocoupling reactions.

Novel dendritic micro–mesoporous TS-1/dendritic mesoporous silica nanoparticle (DMSN) composites (TD) were assembled by TS-1 nanocrystals with ultrasmall particle size and strong acidity. TS-1 seeds and DMSNs were composited via the Ti–O–Si chemical bond, which stimulate the generation of Brønsted (B) and Lewis (L) acids. The spillover d-electrons produced by the Ti element of TS-1 seeds produced a spillover of d-electrons, which could interact with the surface of MoS2phases, thereby reducing Mo–S interactions and create sulfur vacancies that are favorable for dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) hydrodesulfurization (HDS) reactions. The increased amount of B&L acid of NiMo/TD-2.0 with cetyltrimethylammonium bromide/sodium salicylate molar ratio of 2.0 played an important role in facilitating the hydrogenation (HYD) route of DBT HDS and the isomerization (ISO) route of 4,6-DMDBT HDS, which is more favorable for the reduction of steric hindrance of DBT and 4,6-DMDBT reactants in the HDS reaction process. The NiMo/TD-2.0 catalyst exhibited the highest turnover frequency (TOF) value and HDS reaction rate constant (kHDS) of DBT and 4,6-DMDBT due to its ultrasmall particle size, uniform spherical dendritic morphology, strong B&L acidity, and good stacking degree.

We studied the mechanism of the pyrrole synthesis catalyzed by a PN3P–Mn pincer ligand system and show that a bifunctional double hydrogen transfer mechanism is favored over the alternative β-hydride elimination. Both dehydrogenation and hydrogen-formation steps benefit from proton shuttles, with alcohol-mediated processes being consistently favored, leading to energy barriers that, in good agreement with the experimental results, are similar to those for the previously reported corresponding iridium-catalyzed process. We also show that the coordination of one potassium ion to the ligand lowers the energy barriers for the key steps. The overall rate-determining step is the regeneration of the catalyst with an energy barrier of 30.7 kcal/mol with potassium and 31.1 kcal/mol without potassium. Our results support the involvement and the importance of the aromatization/dearomatization paradigm in the reaction.

A radical-based asymmetric olefin difunctionalization strategy for rapidly forging all-carbon quaternary stereocenters α to diverse azaarenes is reported. Under cooperative photoredox and chiral Brønsted acid catalysis, cyclopropylamines with α-branched 2-vinylazaarenes can undergo a sequential two-step radical process, furnishing various valuable chiral azaarene-substituted cyclopentanes. The use of the rigid and confined C2-symmetric imidodiphosphoric acid catalysts achieves high enantio- and diastereo-selectivities for these asymmetric [3 + 2] cycloadditions.

Gastrointestinal stromal tumors (GISTs) are prototypes of stem cell factor receptor (c-KIT)-driven cancer. Two receptor tyrosine kinases, c-KIT and fms-tyrosine kinase (FLT3), are frequently mutated in acute myeloid leukemia (AML) patients, and these mutations are associated with poor prognosis. In this study, we discovered a multitargeted tyrosine kinase inhibitor, compound 15a, with potent inhibition against single or double mutations of c-KIT developed in GISTs. Moreover, crystal structure analysis revealed the unique binding mode of 15awith c-KIT and may elucidate its high potency in inhibiting c-KIT kinase activity. Compound 15ainhibited cell proliferation and induced apoptosis by targeting c-KIT in c-KIT-mutant GIST cell lines. The antitumor effects of 15awere also demonstrated in GIST430 and GIST patient-derived xenograft models. Further studies demonstrated that 15ainhibited the proliferation of c-KIT- and FLT3-driven AML cells in vitro and in vivo. The results of this study suggest that 15amay be a potential anticancer drug for the treatment of GISTs and AML.

Copper (Cu) nanocomposite catalysts with gallium (Ga) and aluminum (Al) were prepared using the simultaneous co-precipitation digestion method. The catalysts were characterized by N2adsorption, N2O titration, XRD (X-ray diffraction), H2-TPR (H2temperature-programmed reduction), XPS (X-ray photoelectron spectroscopy), and CO2-TPD (CO2temperature-programmed desorption) techniques, and CO2hydrogenation to methanol synthesis was performed. The use of Ga in Cu catalysts enhanced the weak basic sites more than the Cu catalysts with Al. With the CuGa nanocomposite formation, the catalyst showed a sequential reduction of CuO, for example, Cu+2to Cu+to Cu0, and the Cu surface area was also high in comparison with CuAl. These findings confirmed that both the Cu surface area and CuO reducibility in the catalyst helped to boost the conversion of CO2, whereas selectivity to methanol was associated with the basicity of the catalyst. CuAl catalysts showed very poor selectivity to methanol despite CO formation, which could be due to the weak interaction of the CuAl nanocomposite catalysts compared to the CuGa nanocomposite catalysts.

Room-temperature photoactivation of the first- and second-generation PN3P-pincer nickel azido complexes 1aand 1bin the presence of CO2or CS2afforded N-bound carbamates, dithiocarbamates, and isothiocyanates, providing insights into CO2and CS2activation and demonstrating how a seemingly small difference in the ligand structure significantly influences the reactivity. Theoretical calculations disclosed that the charge of the phosphorus atom plays a critical role in determining the nitrogen atom transfer to form a plausible nickel phosphiniminato intermediate.

The atom-economical reaction of carbon dioxide (CO2) with epoxides possesses the potential to utilize captured CO₂ for synthesizing useful chemicals. Among a wide range of metal complexes employed for this transformation, iron (Fe) stands out because of its low cost, ready availability, and stability. In this work, a pyridine-based pincer PN³-Fe(II) complex was synthesized and used as an efficient catalyst for the CO₂ epoxide cycloaddition. More importantly, this complex enabled the direct capture of CO₂ in the atmosphere and conversion into cyclic carbonates in excellent yields.

Experimental and computational studies illuminating the factors that guide metal-centered stereogenicity and, therefrom, selectivity in transfer hydrogenative carbonyl additions of alcohol proelectrophiles catalyzed by chiral-at-metal-and-ligand octahedral d6metal ions, iridium(III) and ruthenium(II), are described. To augment or invert regio-, diastereo-, and enantioselectivity, predominantly one from among as many as 15 diastereomeric-at-metal complexes is required. For iridium(III) catalysts, cyclometalation assists in defining the metal stereocenter, and for ruthenium(II) catalysts, iodide counterions play a key role. Whereas classical strategies to promote selectivity in metal catalysis aim for high-symmetry transition states, well-defined low-symmetry transition states can unlock selectivities that are otherwise difficult to achieve or inaccessible.