Small Methods最新文献

Electrolytes critically influence the electrochemical performance and cycle life of lithium ion batteries (LIBs). This holds especially for organic redox polymer-based batteries, such as those employing poly(3-vinyl-N-methylphenoxazine) (PVMPO), where solubility limits performance in conventional ethylene carbonate (EC)/ dimethyl carbonate (DMC)-based electrolytes. Reducing EC content has shown solubility suppression when using ethyl methyl carbonate (EMC) as a co-solvent, however, capacity fading persists due to PVMPO electrode degradation. To address this degradation, this study explores the use of EC-free electrolytes, with and without fluoroethylene carbonate (FEC). Electrochemical investigations, UltraViolet/Visible (UV/Vis) spectroscopy, post-cycling Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) mapping, and X-ray Photoelectron Spectroscopy (XPS) analyses are employed to evaluate solubility, interfacial properties, and electrode integrity. The EC-free electrolyte system with FEC retains 95 mAh g^‒1, while that without FEC retains 86 mAh g^‒1, outperforming the 76 mAh g^‒1 observed in EC-based systems after 500 cycles at 1C. FEC containing electrolyte systems display reduced interfacial resistance, fewer surface cracks, and minimal electrode degradation. These findings demonstrate that EC-free electrolytes, particularly with FEC, effectively suppress electrode degradation and enhance the cycle life of organic LIBs.

Intercalation-based exfoliation offers a cost-effective approach to producing 2D materials. While molecular intercalation surpasses ionic methods in preserving the crystallinity and intrinsic properties of 2D materials, its broader adoption is limited by weak driving forces and slow kinetics. To address these challenges, we propose an interlayer modulation strategy using H₃PO₄-amine complexes as mediators. Structural and molecular dynamics analyses demonstrate that these complexes regulate interlayer proton activity through strong hydrogen bonding, thereby optimizing interlayer dynamics to enable in situ PW₁₂ formation and efficient graphite exfoliation. The PW₁₂ intercalant shows excellent recyclability via simple alkaline hydrolysis and regeneration, establishing a sustainable route for graphene production. This work overcomes the barrier to molecular intercalation by rationally engineering complex molecular intercalation, achieving universal and high-throughput exfoliation of van der Waals layered materials.

Selenium is experiencing renewed interest as a elemental semiconductor for a range of optoelectronic and energy applications due to its irresistibly simple composition and favorable wide bandgap. However, its high volatility and low radiative efficiency make it challenging to assess structural and optoelectronic quality, calling for advanced, non-destructive characterization methods. In this work, we employ a closed-space encapsulation strategy to prevent degradation during measurement and enable sensitive probing of vibrational and optoelectronic properties. Using temperature-dependent Raman and photoluminescence spectroscopy, we investigate grown-in stress, vibrational dynamics, and electron-phonon interactions in selenium thin films synthesized under nominally identical conditions across different laboratories. Our results reveal that short-range structural disorder is not intrinsic to the material, but highly sensitive to subtle processing variations, which strongly influence electron-phonon coupling and non-radiative recombination. We find that such structural disorder and grown-in stress likely promote the formation of extended defects, which act as dominant non-radiative recombination centers limiting carrier lifetime and open-circuit voltage in photovoltaic devices. These findings demonstrate that the optoelectronic quality of selenium thin films can be significantly improved through precise control of synthesis and post-deposition treatments, outlining a clear pathway toward optimizing selenium-based thin film technologies through targeted control of crystallization dynamics and microstructural disorder.

Cancer remains a leading cause of premature mortality worldwide. Targeted drug delivery therapies that selectively attack malignant cells while sparing healthy tissue are essential to minimize side effects and reduce drug dosages. The sodium-potassium ATPase (Na⁺/K⁺-ATPase), particularly its catalytic α-subunit, is overexpressed in A549 non-small cell lung cancer (NSCLC) and has thus emerged as a potential therapeutic target. Cardiac glycosides (CGs), plant-derived secondary metabolites, specifically bind and inhibit this enzyme providing target engagement. Coupling CGs to a biocompatible carrier provides a promising new approach for a targeted-orientated drug carrier. Among these nanocarrier systems, cell-derived extracellular vesicles (EVs) gained attention due to their biocompatibility, tumor-targeting capability, and ability to encapsulate compounds. Here, we developed a target-oriented nanocarrier system by linking 3β-azido-3-deoxydigitoxigenin (CA), a semi-synthetic cardenolide derivative, to the surface of A549 cell-derived EVs. The EVs were characterized for particle concentration, size and protein markers. Surface modification was achieved via alkyne modification and click chemistry. Successful conjugation was confirmed by inhibition of the Na⁺/K⁺-ATPase activity. Co-localization of CA-modified EVs with the Na⁺/K⁺-ATPase was verified by confocal microscopy. Doxorubicin-loaded, CA-modified EVs reduced A549 cell viability to 45% after 48 h, demonstrating its potential use as new drug nanocarrier system.

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Using density functional theory and deep-learning molecular dynamics, in article number 2500683, Kou and co-workers show that polar domains emerge and can be manipulated in twisted bilayers of ferroelectric CuInP₂S₆. Their thermal stability and polarization lifetimes are sensitive to twist angle and temperature, and tunable by external electric fields and strain, offering a pathway to control local polarization through rotational manipulation.

Front Cover

In article number 2500162, Wang, Liebi, and co-workers demonstrate the first high-throughput application of small-angle X-ray scattering tensor tomography (SAS-TT) on a macromolecular crystallography beamline. The image visualizes the collagen fiber network in the human incus, highlighting SAS-TT's potential for fast, non-destructive nanoscale imaging in life science research.

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A composite visual of the Marangoni bursting phenomenon, built from binarized cutouts of experimental snapshots arranged in an azimuthal pattern. Each segment captures the characteristic burst formed when a water-alcohol droplet spreads on an oil bath. To highlight the role of viscoelasticity, a continuous color gradient has been overlaid across the image, following the azimuthal direction. As the viewer moves clockwise, both the color and the polymer concentration, i.e., viscoelasticity, increase. More in article number 2500749, Sen and co-workers.

X-ray scattering is a highly versatile characterization method and has seen widespread use across all fields of science. Previous review articles pertaining to small- and wide-angle X-ray scattering (SWAXS) have either been highly specific or narrow in scope. Generally, other SWAXS reviews have been mainly tailored toward characterizing biological protein samples or polymers. However, there appears to be a literature gap in how SWAXS may be used in characterizing self-assembled systems, more specifically, liquid crystals. SWAXS is a crucial technique used for characterizing liquid crystals, offering valuable crystallographic insights that cannot be directly observed by optical or spectroscopic methods. Unlike spectroscopic techniques, SWAXS can provide valuable nanoscale structural information over a larger volume of material, and it will be discussed in detail herein. This review seeks to fill that gap as well as aid in educating and welcoming prospective scientists interested in learning to use the technique for materials characterization. Several studies will be covered on how SWAXS was used to characterize the most common self-assembled phases.

Selectively dispersed Ru nanoparticles (NP ∼3 nm) on WS₂ nanosheets (NS) (WS₂@Ru) are synthesized by a two-step strategy-plasma exfoliation of bulk WS₂ into nanosheets and subsequent in situ polyol reduction. The dispersion of Ru NP near WS₂ NS edges is confirmed with transmission electron microscopy and predicted with a much larger binding energy for Ru NP on edges than on basal planes (-11.01 vs. -8.41 eV) with density function theory (DFT) calculation. X-ray absorption near-edge spectroscopy reveals electron transfer from Ru to W. WS₂@Ru3 (6 wt.% Ru NP) sample shows optimal hydrogen evolution reaction (HER) activity with an overpotential of 83 mV at 10 mA cm^{- 2} and a Tafel slope of 56 mV dec^-1, significantly smaller than those of pristine WS₂ NS (283 mV and 146 mV dec^-1), and WS₂@Ru3 retains excellent stability after 1000 cycles. DFT calculations also show lower Gibbs free energies of hydrogen adsorption (-0.21 eV) at WS₂@Ru3 edge sites, indicating favorable HER. These enhancements are attributed to the synergistic interaction between Ru NP and WS₂ nanosheets that modulates the electronic structure at the active sites. Our approach of creating a selectively-dispersed 0D/2D heterostructure offers a sustainable and scalable strategy for fabricating superior electrocatalysts for hydrogen production.