Advanced Materials Interfaces最新文献

Silicon-based negative electrodes are essential for next-generation high-capacity Li-ion batteries, with SiO₂ emerging as a promising and sustainable option. However, SiO₂ anodes have limited cycling stability, which can be improved by tailoring the solid electrolyte interphase (SEI) through electrolyte engineering. This study investigates the effects of LiPF₆ and LiFSI electrolyte salts, along with fluoroethylene carbonate (FEC) and vinylene carbonate (VC) additives, on the performance of SiO₂ anodes. Galvanostatic cycling and electrochemical impedance spectroscopy (EIS) are combined with SEI composition analysis using Ar⁺-sputtered X-ray photoelectron spectroscopy and hard X-ray synchrotron photoelectron spectroscopy at different photon energies. The results show that FEC enhances capacity retention, while VC improves long-term stability at the expense of lower initial capacity. No synergistic benefits are observed from combination of both additives. LiFSI-based electrolytes deliver high initial capacities but suffer capacity fade over cycling, whereas additive-free LiPF₆ formulations lead to poor cycling stability due to the formation of a thick and resistive SEI layer. In contrast, LiFSI promotes a thinner and more inorganic-rich SEI. Both FEC and VC lead to the formation of a poly(VC) surface layer that enhances capacity retention. The FEC-derived layer, enriched with LiF and thinner in nature, exhibits improved SEI stability. These findings provide valuable insights for designing electrolytes to improve the cycling performance of SiO₂ anodes.

The underwater functionality of superhydrophobic (SHPo) surfaces relies on the presence of a thin trapped air layer, or plastron, yet maintaining this plastron in uncontrolled environments remains a major challenge. Here, a scalable method is reported to convert SHPo surfaces into Salvinia surfaces by selectively coating polydopamine (PDA) on the top surfaces of microstructures. The success is enabled by identifying and overcoming a previously unrecognized barrier unique to PDA coating on SHPo surfaces. Pressure fluctuation experiments demonstrate that the converted Salvinia surfaces have markedly enhanced plastron stability compared with SHPo counterparts of identical microstructure. Complementary mathematical analysis and numerical simulations establish how micrograting and micropost geometries govern plastron stability, providing a design guideline for SHPo and Salvinia surfaces.

Catheter-associated infections are a major concern in hospitals, leading to both life-threatening for the patients and a high cost for society. The development of a straightforward and industrial route to make an antibacterial catheter is thus worthwhile. This study demonstrates that the use of 2 wt.% of an antibacterial MeI-quaternized poly(butyl methacrylate–block–N,N-dimetylaminoethyl methacrylate) P(BMA-b-DMAEMA) copolymer in combination with 2 wt.% of an antiadhesive poly(butyl methacrylate–block–poly(ethylene glycol) methyl ether methacrylate) P(BMA-b-PEG_xMA) copolymer (with x the molecular weight of the PEG) as additives during the extrusion of the polyurethane matrix is an efficient method to produce antibacterial and antiadhesive PU materials without loss of activity after exposure to biologic media. The addition in the formulation of the antiadhesive copolymers enables protecting the surface from passivation and then to keep the contact possible between the bacteria and the antibacterial material. The antibacterial activity of the materials against E. coli and S. aureus is then preserved even after exposure to albumin, plasma, intralipids, or gastric acids. The prepared biomaterials also present no toxicity and are able to limit E. coli biofilm formation. Based on these results, this methodology can be realistically envisioned to elaborate long-lasting venous or enteral catheters.

Ru₃Sn₇ is experimentally demonstrated as an efficient catalyst, with potential utilization of topological surface states for hydrogen evolution reaction. Despite its promising catalytic performance, the topological nature of Ru₃Sn₇ remains uncertain. Particularly, the bulk-boundary correspondence has not yet been established, hence hindering a rigorous justification of its topologically-protected surface states. In this work, the bulk topology of Ru₃Sn₇ is detailed using first-principles calculations and the topological quantum chemistry formalism. Ru₃Sn₇ turns out to be an enforced semimetal possessing symmetry-protected crossings within a set of bands near the Fermi level, which are enforced and prescribed by the violations of symmetry-prescribed compatibility relations. Moreover, the surface states and the associated origin from the same set of entangled bands are identified, thereby establishing the bulk-boundary correspondence. To evaluate the effects of chemical modifications, the response of topological surface states to various surface terminations, stoichiometry, and oxidation is examined. The surface structures are globally optimized, and the phase diagrams for various experimental conditions are built. It is shown that, due to changes in the local chemical environment, the original surface states are significantly altered. Modified surface bands can be observed near the Fermi level on surface terminations that preserve the C_4v symmetry.

Solutions containing hydrofluoric acid (HF) and bromic acid (HBrO₃) are investigated as nitrogen oxide (NO_x)-free mixtures for wet-chemical etching of (100) silicon wafer surfaces. Isotropic etching behavior with high dissolution rates of up to 10 µm min⁻¹ is observed at room temperature, leading to polished surfaces. Anisotropic etching is observed when bromine (Br₂) is added to HF-HBrO₃ solutions. Therefore, monocrystalline (100) silicon wafer surfaces are covered with random upright pyramids with edge lengths of about 5 µm. The etch rate is strongly dependent on the concentration of HBrO₃. Silicon surfaces are analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The gas phase is analyzed using Raman and infra red (IR) spectroscopy. The oxidation of the silicon surface by bromic acid likely takes place via oxygen insertion into the rearward silicon bonds. During etching, multiple active Br-species are formed which alter the etching behavior.

Surface functionalization is essential for improving polymer properties like wettability and wear resistance. Polydimethylsiloxane (PDMS) is widely used due to its flexibility, biocompatibility and ease of fabrication. Soft lithography—based on molding and replication—is the most common approach to tailor its wettability, but producing high-quality molds remains complex and time-consuming, calling for faster, cost-effective and reproducible alternatives. In this work, a novel femtosecond laser-based technique is presented for the rapid and precise fabrication of aluminum molds for PDMS replication. By tuning hatch distance and scan number as key process parameters, the resulting surface morphology of the PDMS replicas is controlled. The samples are characterized morphologically and by profilometry; the reproducibility of the laser-engraved molds and the effect on the final PDMS surfaces is assessed, alongside wettability measurements as a function of the processing parameters, achieving superhydrophobic behavior under optimized conditions. Long-term testing over 4 months confirmed the stability and durability of the surface properties, highlighting their potential for applications in self-cleaning systems, droplet-based microfluidics and biomedical devices.

The efficient and stable capture of cells within microfluidic platforms is essential for cellular biology analyses, offering insights into the heterogeneity of cell properties and cellular processes, for example, among cancer cells. However, conventional microfluidic cell confinement modalities, such as water-in-oil emulsions and microstructure trapping, face inherent limitations in biological applicability and precise control. Here an approach is introduced to confine cells in dead-end microstructures leveraging a dextran concentration gradient. This method allows for the fine-tuned capture of cells, reaching the precision of single-cell culture, as demonstrated for yeast and leukemia cells. By incorporating polyethylene glycol (PEG) solutions, phase separation is induced within the microfluidic environment, encapsulating single cells within dextran droplets. The technique is distinguished by its stability, control, and adaptability, paving a new way for innovations not only in cellular biology, but broadly in chemical and biological applications, including the synthesis of bio-oriented particles, microcarrier production, and advancements in tissue engineering.

Epitaxial thin-film heterostructures of the strongly spin-orbit coupled Mott-insulator Sr₂IrO₄ (SIO) and the cuprate high temperature superconductor YBa₂Cu₃O_{7 − δ} (YBCO) are grown with pulsed laser deposition (PLD). A high crystalline quality is confirmed with X ray diffraction. The magnetic order of single SIO layers is studied with dc magnetization and low-energy muon spin rotation measurements and resembles that of the bulk material with a canted antiferromagnetic order. The electronic normal state and superconducting properties of YBCO (10, 12, or 14 nm)–SIO (20 nm) and inversely stacked SIO (20nm)–YBCO (10, 12, or 14 nm) bilayers are studied with dc resistivity measurements and found to be strongly dependent on the sequence of the layer stacking. The YBCO–SIO bilayers with d(YBCO) = 14nm, 12 nm, and 10 nm are all metallic and superconducting with an onset temperature around 85K and zero resistivity below 65K. To the contrary, for the inversely stacked SIO–YBCO bilayers a metallic and superconducting response occurs only at d(YBCO) = 14 nm, whereas $��d�\left(�\mathrm{YBCO}�\right)�=�12��\mathrm{nm}�$ and 10 nm are electronic insulators. This highlights that a long-ranged localization and/or depletion of the YBCO charge carriers occurs at the SIO–YBCO interface that is very anomalous and remains to be understood.

Carbon-based films are widely used in technologies requiring surfaces with controlled wettability. These films can be synthesized by depositing carbon nanoparticles (CNPs) onto substrates intermittently inserted into rich premixed flames, where thermophoresis drives particle capture. Depending on flame conditions, this method yields either hydrophilic films (from incipient sooting flames) or superhydrophobic films (from fully sooting flames). However, under incipient sooting conditions, the low concentration and small size of CNPs result in slow deposition, limiting practical applications. This study explores Electric Field-Assisted Thermophoretic Flame Synthesis (E-ThFS) as a strategy to enhance deposition. Rich ethylene/air flames are used, and the effect of an external electric field is investigated. UV–vis spectroscopy, profilometry, and contact angle measurements show that applying a −3 kV electric field accelerates deposition up to fivefold and alters surface morphology, producing more heterogeneous textures. The hydrophilic character of films from incipient sooting flames is preserved, although it may be preceded by a brief metastable superhydrophobic state whose duration decreases as voltage increases. In fully sooting flames, the electric field similarly enhances deposition and roughness while maintaining superhydrophobicity. These findings demonstrate the potential of E-ThFS as a scalable, one-step method for creating carbon coatings with tunable wettability and morphology.

Surface design aimed at regulating the behavior of endothelial cells is currently a key research direction in cardiovascular interventional/implantable materials. This review focuses on three primary regulatory strategies in material biology: direct regulation, protein-mediated regulation, and biological factor regulation. These strategies aim to promote the recovery of endothelial cell function by optimizing the interaction between materials and blood, cells, and tissues. Furthermore, these surfaces also exhibit diverse effects in vivo on different types of cells. It is precisely due to the complex factors and diverse effects in the pathological environment that these macro-to-micro regulation strategies exhibit opposing states on the material-tissue efficacy interface. Therefore, this series of design ideas still faces challenges in practical applications, including time-sequential functional changes after implantation, how to maintain protein activity in complex pathological environments, and how to accurately control the release of biological factors. The study concludes by emphasizing that the endothelialization surface modification of stent materials is moving towards multidimensionality, including exploring the synergistic effects of these strategies and how to achieve optimal therapeutic outcomes under various pathological conditions, in order to develop more effective and safer vascular stent materials and provide new solutions for the treatment of cardiovascular diseases.