Sodium-ion batteries (SIBs) are promising next-generation batteries as a sustainable alternative to lithium-ion systems, yet an understanding of the solid electrolyte interphase (SEI) is far from sufficient. Here, we develop a probing approach using redox mediator molecules to characterize subnanometric SEI pores, revealing that Na+ transport occurs through diffusion channels. By electrochemical analysis, differential electrochemical mass spectrometry, and theoretical calculations, the influences of solvent salts on SEI architecture have been studied. These findings offer fundamental knowledge beyond classical SEI models and provide both a powerful characterization tool and principles for electrolyte choice for SIBs.

A novel approach for the surface-initiated atom transfer radical polymerization (SI-ATRP) of methoxyethyl methacrylate (MEMA) and 3-azidopropyl methacrylate (AZMA) on macroporous silicon substrates and their postfunctionalization by click chemistry with asymmetric catalysts is presented. Crystalline silicon was first used to monitor the multistep functionalization by quantitative IR-ATR spectroscopy. The attachment of an alkynyl FTIR marker on crystalline silicon demonstrated the effectiveness of the methodology, which was then applied onto macroporous silicon to anchor an enantiopure chromium-salen complex as a first step toward the development of new supported asymmetric organometallic catalysts on silicon-based materials. SEM and EDS measurements clearly show good homogeneity of the polymer growth through the porous layers with a uniform distribution of the catalysts (even deep inside the pores). The successful functionalization of macroporous silicon has confirmed the transferability of the technique to porous materials, highlighting its potential for application to even larger surface area substrates in future catalytic studies.

This study investigates the heat-flux enhancement of convection flows inside a fluid layer bounded from the top and bottom by two inhomogeneous porous layers. The porous matrix is made of solid materials with very high diffusivity. The numerical results reveal that, compared with the traditional convection system, the heat flux is greatly increased when the thickness of porous layer is large enough. At small Rayleigh numbers, the enhancement is the result of the increase in effective diffusivity in the fluid-saturated porous layers and the reduction in flow friction at the porous interface. For large Rayleigh numbers, the permeable motions across the interfaces generate strong convective flux, which greatly increases the total heat flux. For the latter parameter range, the exponent of the power-law scaling between the Nusselt number and the Rayleigh number exceeds 1/2, which is the value of the ultimate scaling. Our findings are not only of great potential in heat management in various industrial applications but also imply that, in many natural systems with imperfect boundaries, the global heat flux may be much stronger than the prediction by using a convection system with perfect boundaries.

Developing high‐activity, low‐platinum‐loading catalysts for the oxygen reduction reaction (ORR) is crucial for proton exchange membrane fuel cells (PEMFCs). This work presents a novel strategy to enhance the performance of PtCo catalysts by combining multilayer magnetron sputtering with postacid treatment. PtCo catalysts with varying architectures (cosputtered, two, four, and six layers) were deposited onto SGL carbon paper. The results indicate that the ORR activity is strongly influenced by the catalyst layer thickness and sputtered modes, with the four‐layer structure exhibiting the optimal balance. More importantly, acid treatment of the four‐layer catalyst selectively leached Co, as confirmed by XPS, resulting in a microporous Pt‐rich structure. This structural evolution significantly increased the electrochemical active surface area (ECSA) from 43.5 to 58.6 m 2 /g. Consequently, the acid‐treated catalyst achieved a remarkable mass activity of 0.31 A/mg at 0.9 V versus RHE, which is the highest among all samples, and it also demonstrated superior durability in accelerated degradation tests. This study demonstrates that architecting catalyst layers through multilayer sputtering followed by acid leaching is an effective approach for creating high‐performance, porous ORR catalysts.

Effect of porous layers and array geometry on thermal management in air-cooled lithium-ion battery modules during high-rate cycling

Guided bone regeneration (GBR) has gained significant attention in the field of bone tissue engineering. However, designing an effective barrier membrane that simultaneously meets the mechanical and biological requirements at the soft-hard tissue interface remains a considerable challenge. Herein, weintroduce a combinatorial assembly strategy to construct a continuous Janus membrane with multiscale architectural features inspired by biological materials. Structurally, the membrane features an asymmetric design, comprising a compact layer with a Bouligand architecture that incorporates amorphous calcium phosphate (ACP) to enhance mechanical strength and prevent soft tissue infiltration, and a porous layer that recapitulates the trabecular structure of cancellous bone, enriched with hydroxyapatite (HAp) crystals to promote cellular adhesion and osteoinduction. Subsequent in vitro and in vivo results show that the membrane not only exhibits excellent biocompatibility and barrier function but also significantly enhances osteogenic differentiation and bone regeneration in a cranial defect model. This work demonstrates that integrating diverse fabrication techniques enables the creation of functionally efficient GBR membranes with hierarchical structures, offering a promising pathway toward multifunctional regenerative materials.

Comparison of non-Newtonian models in a bearing with a porous layer: Viscoelastic (Maxwell) versus micropolar (couple stress)

Synergistic effect of flow field and porous transport layer matching on mass transfer and early-stage degradation mitigation in PEMWE under high operating current densities

Bio-derived porogens architecting sintered-titanium porous transport layers for performance-enhanced PEM water electrolysis

How much platinum is enough? Stability of Pt-coated titanium films for porous transport layers (PTLs) in acidic and fluoride-containing electrolyte

Performance enhancement of proton electrolyte membrane (PEM) water electrolyzers through modification of titanium-based porous transport layers (Ti-PTLs): A review

Artificial neural network approach for the prediction of onset of magneto-convection of a power-law nanofluid saturated porous layer

Evaluation of osteoporosis features in cortical bone models using pattern recognition methods applied to ultrasound data.

We present a one-dimensional photonic crystal biosensor based on a Thue-Morse quasi-periodic structure incorporating parity-time (PT) symmetry and exceptional point (EP) engineering for enhanced cancer detection. By integrating alternating porous silicon gain-loss layers with graphene nanolayers, the proposed design achieves strong optical confinement and pronounced resonance sharpening near EP conditions. A systematic parametric study identified the optimal graphene chemical potential and relaxation time as 0.408eV and 0.5 ps, respectively, leading to a maximum sensitivity of 1054nm/RIU and a minimum detection limit of 9.875 × 10- 4 RIU. Moreover, the analysis reveals that increasing the number of graphene layers results in a progressive enhancement in sensitivity accompanied by a reduction in the optimal porosity percentage, highlighting the strong influence of graphene-induced field confinement on device performance. These results surpass those of conventional one-dimensional biosensors, demonstrating the combined advantages of PT symmetry and graphene-assisted field enhancement. Fabrication tolerance analysis confirmed the structural robustness, underscoring its potential for practical implementation. Overall, the findings establish PT-symmetric Thue-Morse photonic crystals as a versatile platform for ultra-sensitive, label-free biomedical sensing, paving the way for next-generation optical diagnostic technologies.

Direct seawater electrolysis for hydrogen production is hindered by severe catalyst inactivation and material corrosion caused by the complex composition of natural seawater. In this work, we demonstrate a multistage structure on a stainless steel (SS) substrate by integrating Pt atomic clusters (0.044 wt%) with a dense NiFe layer double hydroxides (NiFe-LDH) anticorrosive coating. The assembled seawater electrolyzer maintains durable operation for 600 h at a current density of 400mA cm-2 (∼2.04V) and for 1000 h at 200mA cm-2 (∼1.78V), while simultaneously achieving a cost reduction of more than 40% and ultralow energy consumption of 4.26kWh Nm-3 H2. Multiple in situ characterization results reveal that the adsorbed H2O molecules between the interface of Pt atomic clusters and NiFe-LDH could initiate a potential-driven dynamic transformation process from a 4 hydrogen-bond to a 0 hydrogen-bond coordination of H2O, thereby promoting their dissociation. Pt atomic cluster induces a configuration transformation of interfacial water from two-H down to two-H up and differentiates the adsorption energies between H2O and chloride ions, further optimizing selectivity. This work fully demonstrates the integrated design of catalysts, anti-corrosion coating, and porous transport layer, thereby offering an innovative and practical approach to direct seawater electrolysis.

Abstract The study presents an industrial-scale evaluation of two PEM electrolyser stacks incorporating Naco-engineered titanium coatings on porous transport layers (PTLs) and bipolar plates. Stack 0316/44 included both coated PTLs and coated bipolar plates, while Stack 0317/44 utilised only coated PTLs. Both stacks were conditioned for 40 hours at 15 bar and subsequently tested at current densities of 0.6 and 1.2 A cm −2 . At 150 A, the total voltages measured were 89.8 V for 0316/44 and 88.9 V for 0317/44, whereas at 300 A, they reached 99.3 V and 102.8 V, respectively. Gas purity remained within safe limits, with residual oxygen (O 2 ) in hydrogen (H 2 ) ranging from 14 ppm to 31 ppm and H 2 crossover remaining below 0.7 % across all tests. Integrated operation in the SIRIO 1000 system at 300 A produced the combined voltages of 106.0 V and 104.0 V for the two stacks. Average power consumption during joint operation was 5.75 kW/Nm³, approximately 10–20 % higher than that of standard industrial stacks. The results confirm the stable operation and acceptable gas-separation performance of the coated components under high-pressure, high-current conditions, while also identifying efficiency gaps that require further optimisation. The study provides the first comparative industrial assessment of the coated PEM stack architectures and establishes a foundation for future durability and optimisation studies.

Hard carbon (HC) materials featuring well‐defined short‐range ordered architectures have emerged as promising anode materials for sodium‐ion batteries (SIBs). Nevertheless, due to the limited diffusion rate of sodium ions within the carbon structure, the rate capability of hard carbon at high current densities and long‐term cycling stability remains a challenge. Herein, an innovative nitrogen/sulfur co‐doping strategy is developed for loofah‐derived hard carbon (LHC‐N‐S), synergistically regulating the electron defect and spatial structure. The synergistic charge regulation is attributed to the introduction of N atoms for ion adsorption and the improvement of electron conductivity. The spatial structure regulation mainly comes from the S doping to optimize the layer spacing and pore size, which facilitates the rapid ion diffusion kinetics. The obtained LHC‐N‐S anodes maintain a high reversible specific capacity (317.5 mAh g −1 at 0.1 C) and ultralong lifespan (76% retention after 2000 cycles). Through the correlation analysis of the structural parameters and the Na + storage performance, the N/S co‐doping mechanism is further clarified. This work provides deep insights into the design of high‐performance biomass‐derived hard carbon anodes for SIBs by leveraging the synergistic charge and space regulation through heteroatom doping, paving the way for the development of durable and sustainable sodium‐ion battery technologies.

The cell surface glycocalyx is a complex and dynamic network of glycoproteins and proteoglycans that plays a pivotal role in life activities. Its three-dimensional architecture is composed of various glycosaminoglycans (GAGs) mediating various biological functions. Exploring the structure of GAGs and its interaction with proteins or the GAGs code is of great significance for revealing the molecular mechanisms of biological processes. However, the structural complexity of the glycocalyx at both cellular and tissue scales poses challenges for accurate representation, while conventional planar sensors inadequately capture its multiscale spatial characteristics, thereby limiting precise analysis of dynamic GAG-protein interactions. In this study, a three-dimensional ordered interference substrate with surface-modified heparin was constructed to simulate the fine topological structure of the glycocalyx. On this ordered porous layer interferometry (OPLI) platform, combined with experimental and computer simulation methods, the effects of heparin density, spatial distribution, and chain length on the binding behavior of SARS-CoV-2 spike protein were systematically investigated. The experimental results show that a medium heparin density can maximize the binding strength of the spike protein. The affinity of heparin for spike protein can be enhanced by increasing the density of the three-dimensional spatial distribution. Molecular docking and thermodynamic experiments suggest that hydrogen bonds rather than electrostatic interactions play a crucial role in the binding strength. This study recreates the glycocalyx microenvironment, providing a highly biomimetic platform that not only deepens the molecular understanding of viral infection but also lays a methodological foundation for GAG code analysis and drug development.

ABSTRACT The rapid development of advanced aircraft has heightened the demand for high‐performance thermal protection systems (TPS), yet existing materials struggle to balance ultra‐high‐temperature ablation resistance and thermal insulation. Inspired by the hair of polar bears, a biomimetic bifunctional composite with a “surface ablation resistance—inner thermal insulation” partitioned structure is designed and fabricated. This architecture comprises a dense ablation‐resistant layer composed of HfC nanoparticles / Carbon microspheres@HfC (HfC‐n/CMs@HfC) and a porous insulation layer consisting of monodisperse HfC hollow microspheres (HfC‐HMs, a material innovation synthesized herein). The composite with a mere 4 mm thickness withstands ablation at 2500°C for 1000 s with a 1638°C front‐back temperature difference, and maintains a 1724°C difference at 2600°C for 100 s. The excellent performance stems from the in‐situ formation of a dense HfO 2 layer by HfC‐n and CMs@HfC, which blocks heat and oxygen, coupled with HfC‐HMs suppressing gas conduction through the Knudsen effect within the hollow microstructure and diminishing solid conduction by phonon scattering at the nanoscale shells. Additionally, the composite exhibits a high compressive strength of 201.44 MPa. This work demonstrates that a composite can balance ablation resistance and thermal insulation, and offers a novel design strategy for next‐generation ultra‐high‐temperature TPS.

In this investigation, we develop basic methods for the multi-scale analysis of problems in thin porous layers. More precisely, we provide tools for the homogenization of “tangentially” periodic structures, and dimensional reduction letting the layer thickness tend to zero prop ortional to the scale parameter ϵ . A crucial point is the identification of scale limits of sequences v ϵ characterized by uniform a priori estimates with respect to ϵ , arising as solutions of differential equations, like Navier–Stokes system, linear elasticity, or fluid-structure interaction problems, in media with thin layers. Often in such problems, in a first step, the symmetric gradients can be controlled, and Korn’s inequality in porous layers is required to estimate the gradients. We construct controllable pore-filling extensions and use them for the proof of the required Korn-inequalities in L p -spaces. These results are the basis for the derivation of compactness results with respect to two-scale convergence and the characterization of the scale limits. To illustrate the range of application of the developed multi-scale methods, a semi-linear elastic wave equation in a thin periodically perforated layer with an inhomogeneous Neumann boundary condition on the surface of the elastic substructure is treated and a homogenized, reduced system is derived.