Angewandte Chemie最新文献

The influence of coadsorbed ions on adsorbate diffusion, an inherent effect at solid–liquid interfaces, was studied for adsorbed sulfur on Ag(100) electrodes in the presence of bromide or iodide. Quantitative in situ high-speed scanning tunnelling microscopy (video-STM) measurements were performed both in the potential regime of the c(2×2) halide adlayer at its saturation coverage and in the regime of a disordered adlayer where the halide coverage increases with potential. These studies reveal a surprising non-monotonic potential dependence of S_ad diffusion with an initial increase with halide coverage, followed by a decrease upon halide adlayer ordering into the c(2×2) structure. Density functional theory (DFT) and Monte Carlo (MC) simulations only qualitatively reproduce the rise in S_ad mobility with halide coverage, suggesting that many-adsorbate interactions and the presence of the electrolyte need to be considered.

As an emerging class of optoelectronic materials, multi-resonance (MR) 1,4-BN-heteroarenes have been extensively employed as narrowband electroluminescence materials, whereas their absorption feature has largely been neglected. Here we construct the first MR-molecule-based phototransistor for filterless narrowband photodetectors (NBPDs) by anchoring narrowband absorption MR molecules on a high-mobility semiconductor indium-zinc-oxide (IZO) film. The resulting device exhibits high-performance photodetection with a small full-width at half-maximum (FWHM) of 33 nm, which represents a new record for NBPDs based on intrinsic narrowband absorbing materials. These results demonstrate the great potential of MR materials as a new molecular platform for developing high-performance NBPDs.

Nitrogen heterocyclic carbenes (NHCs) are emerging as effective substitutes for conventional thiol ligands in surface functionalization of nanoparticles (NPs), offering exceptional stability to NPs under harsh conditions. However, the highly reactive feature of NHCs limits their use in introducing chemically active groups onto the NP surface. Herein, we develop a general yet robust strategy for the efficient surface functionalization of NPs with copolymer ligands bearing various functional groups. The polymer ligands consist of a multiple NHCs block, utilized for surface binding on NPs, alongside a poly(reactive ester) block intended for incorporating functional groups. The multiple NHCs block enables NPs with excellent colloidal stability across a broader range of pH values (0–14), temperature variations (–78 °C-100 °C), and electrolyte concentrations (0–1000 mM). Through the in situ ammonolysis of the poly(reactive ester) block, various active functional groups can be individually or together introduced on the NP surface. We further demonstrate the chemical reactivity of these functionalized NPs, including addition polymerization, Diels–Alder and Schiff base reactions. This method is applicable to various types of NPs, including metal NPs, metal oxide NPs, and even upconversion NPs, thereby paving new pathways for the design and creation of nanoparticle-based functional materials.

As the “blood” of Li−O₂ batteries (LOBs), electrolytes with various solvation structures of Li⁺ can greatly influence the composition of solid electrolyte interphase (SEI) on anode and the growth kinetics of Li₂O₂ on cathode, and further the battery performance. However, achieving delicate modulation of the multi-composition electrolytes remains significantly challenging to simultaneously give consideration to both the anode and cathode reactions. In this work, we employed Bayesian optimization to develop advanced electrolytes for LOBs, enabling the formation of a stable inorganic-rich SEI, and modulation of Li₂O₂ morphologies. Thus obtained LOBs using the optimized dual-solvent electrolyte could deliver a discharge capacity of 14,063 mAh g⁻¹ at a current density of 500 mA g⁻¹, which is far higher than those using the single-solvent electrolytes. This study not only highlights the critical role of the solvation structure for improving the battery performance, but also provides new insights and important theoretical guidance for delicate modulation of electrolyte compositions.

Hydroxylation, an extensive post-translational modification on proline, is critical for the modulation of native protein structures, further dominating their functions in life systems. However, current mass spectrometry (MS)-based identification, could hardly distinguish hydroxylation with the neighboring oxidation due to the same mass shifts, as well as challenges posed by low abundance and exogenous oxidation during sample preparation. To address this, an engineered nanopore was designed, capable of discriminating single hydroxyl group on proline, to achieve the identification of proline hydroxylation on individual native peptides directly in mixture. By modeling the interaction between hydroxylated proline and its specific recognition protein, we introduced a hydrophobic region in aerolysin lumen with A224Y/T274W mutations to enhance the sensitivity for proline residue. The results showed that the proline hydroxylation on native HIF-1α fragments could be unambiguously identified without purification, which could be maintained even in the presence of neighboring oxidation. The voltage-dependent experiments further demonstrated the more relaxed peptide structure induced by hydroxylation that supported the great impact of hydroxylation on chemical properties of proline and the molecular mechanism of the specific recognition for hydroxylated proline in nature. These findings highlight the potential of nanopore for precise hydroxylation detection, offering a reliable platform for further uncovering the related functions in biological systems.

Lanthanides, which are part of the rare earth elements group have numerous applications in electronics, medicine and energy storage. However, our ability to extract them is not meeting the rapidly increasing demand. The discovery of the bacterial periplasmic lanthanide-binding protein lanmodulin spurred significant interest in developing biotechnological routes for lanthanide detection and extraction. Here we report the construction of β-lactamase-lanmodulin chimeras that function as lanthanide-controlled enzymatic switches. Optimized switches demonstrated dynamic ranges approaching 3000-fold and could accurately quantify lanthanide ions in simple colorimetric or electrochemical assays. E.coli cells expressing such chimeras grow on β-lactam antibiotics only in the presence of lanthanide ions. The developed lanthanide-controlled protein switches represent a novel platform for engineering metal-binding proteins for biosensing and microbial engineering.

The wide application of zeolite Y in petrochemical industry is well-known as one of the milestones in zeolite chemistry and heterogeneous catalysis. However, the traditional organic-free synthesis typically produces (hydro)thermally unstable zeolite Y with Si/Al atomic ratio (SAR) less than 2.5. Inspired by drug delivery process in which active components are kinetically controlled released, we develop a unique approach based on the pre-synthesized aluminum carrier to prepare one of the most siliceous zeolite Y with SAR up to 3.44 without using organics. The crystalline or amorphous aluminophosphates serve as the ideal carrier for the controlled incorporation of Al into zeolite framework during zeolite Y crystallization. Experimental and theoretical results reveal that the partial introduction of aluminophosphate as Al source would rationally regulate the crystallization kinetics, facilitating the formation of high-silica zeolite Y with random Al distribution. This approach enhances the hydrothermal stability and catalytic performance of zeolite Y in benchmark reaction.

Cyclopropanes are prevalent in natural products, pharmaceuticals, and bioactive compounds, functioning as a significant structural motif. Although a series of methods have been developed for the construction of the cyclopropane skeleton, the development of a direct and efficient strategy for the rapid synthesis of cyclopropanes from bench-stable starting materials with a broad substrate scope and functional group tolerance remains challenging and highly desirable. Herein, we present an electrochemical method for the direct cyclopropanation of unactivated alkenes using active methylene compounds. The strategy shows a broad substrate scope with a high level of functional group compatibility, as well as potential application as demonstrated by late-stage cyclopropanation of complex molecules and drug derivatives. Further mechanistic investigations suggest that Cp₂Fe (Fc) plays an essential role as an oxidative mediator in generating radicals from active methylene compounds.

Glycans, unlike uniformly charged DNA and compositionally diverse peptides, are typically uncharged and possess rich stereoisomeric diversity in the glycosidic bonds between two monosaccharide units. These unique features, including charge heterogeneity and structural complexity, pose significant challenges for accurate analysis. Herein, we developed a novel single-molecule oligosaccharide sensor, OmpF nanopore. The natural electroosmotic flow within OmpF generates a robust driving force for unlabeled neutral oligosaccharides, enabling detection at a concentration as low as 6.4 μM. Furthermore, the asymmetric constriction zone of OmpF was employed to construct a stereoselective recognition site, enabling sensitive identification of glycosidic bond differences in cell lysate samples. With the assistance of machine learning algorithms, the OmpF nanopore achieved a recognition accuracy of 99.9 % for tetrasaccharides differing in only one glycosidic bond was achieved. This nanopore sensor provides a highly sensitive analytical tool with a broad dynamic range. It enables chiral recognition of oligosaccharides at low concentrations and is suitable for analysing both low-abundance and practical samples.