Polymer Layer Research Articles

Simulation study on supercontinuum broadening based on the BIC model.

Bound states in the continuum (BIC) refers to waves that are entirely confined within the continuous spectrum of radiation waves without interacting with them. In our study, we attempted to construct a waveguide satisfying BIC conditions by forming a polymer layer on a 4H-SiC substrate, positioned on an S i O 2 insulator. By fine-tuning the waveguide parameters, we minimized losses to the substrate continuum and determined that the lowest loss meeting BIC conditions occurs when the HSQ width is 1.82µm and the 4H-SiC thickness is 440nm. Subsequently, we investigated the supercontinuum generation (SCG) in this waveguide. First, we analyzed the primary linear and nonlinear effects in the SCG process, introducing well-established theoretical frameworks such as the generalized nonlinear Schrödinger equation (GNLSE) for pulse propagation in nonlinear media. We then studied the influence of waveguide parameters on SCG, observing the variations in SCG with different HSQ widths and 4H-SiC thicknesses. Our results indicate that optimal spectral broadening and conversion efficiency are achieved with an HSQ width of 1.82µm and a 4H-SiC thickness of 440nm. In our simulations, the waveguide length was set to 1cm, and the pump pulse was modeled as a Gaussian pulse with a width of 100fs and a peak power of 8W.

Micromolar-level glucose detection using a colorimetric sensor based on imprinted polymer-coated Fe3O4 nanoparticles

The glucose concentration in the blood, commonly referred to as blood sugar level, typically ranges from 3.9 to 5.6 mmol/L. It is one of the most critical physiological parameters in the human body, requiring strict regulation to maintain proper bodily function. There is a strong demand for glucose sensors that are highly sensitive, user-friendly, and exhibit high selectivity towards glucose molecules, even in challenging environments. In this study, a colorimetric sensor based on imprinted polymer and Fe3O4 nanoparticles (NPs) was developed, enabling the detection of glucose at micromolar levels, observable by the naked eye. Fe3O4 NPs were prepared using a sol–gel method and served as cores for the deposition of polydopamine (PDA) via in situ polymerization. An imprinting process created glucose-imprinted PDA, resulting in molecular cavities on the PDA surface, with the polymeric layer approximately 25 nm thick. The surface of the Fe3O4 NPs facilitated the degradation reaction of H2O2 to produce hydroxyl radicals (•OH), which subsequently oxidized 3,3′,5,5′-Tetramethylbenzidine (TMB) to its oxidized form (TMB+), causing a color change from colorless to blue. The cavities played a crucial role in the sensing mechanism, connecting the catalytic surface of the Fe3O4 NPs to the surrounding environment. When glucose molecules occupied the cavities, the catalytic activity decreased, leading to a corresponding variation in color change depending on glucose concentration. Leveraging these advantages, the imprinted PDA was applied to detect glucose in aqueous solutions and human plasma with a limit of detection as low as 10 µM. The sensor exhibited high selectivity towards glucose over other common analytes in human blood, such as lysine, Ca2+, and K+, along with reproducibility, maintaining approximately 73 % of its sensing signal after six cycles of reuse. This study demonstrates the detection of glucose by the naked eye at micromolar levels. The detection procedure can be conducted outside of laboratory settings, presenting a highly promising approach for glucose detection in real-world applications, particularly in remote areas.

Formation of Hybrid Membranes for Water Desalination by the Method of Membrane Distillation

A method has been developed for the formation of hybrid membranes consisting of a hydrophilic microporous substrate and a hydrophobic nanofiber polymer layer deposited by electroforming. A track-etched membrane made of polyethylene terephthalate was used as a hydrophilic microporous substrate, on the surface of which a thin layer of titanium was applied by magnetron sputtering to ensure adhesion of the nanofiber layer. Simultaneously, the titanium coating was used to make a conductive track-etched membrane that served as a collector electrode. It is been shown that the application of this method for the formation of polymer coatings when used as a starting material for the formation of polyvinylidene fluoride nanofibers makes it possible to obtain a layer with highly hydrophobic properties, the water contact angle of the surface of which, depending on the deposition density, averages 143.3 ± 1.3°. A study of the morphology of the nanofiber coating shows that it has a microstructure typical of non-woven materials. The nanofibers forming the porous system of this layer have a wide range in size. The study of the molecular structure of the nanofiber layer by IR-Fourier spectroscopy and X-ray diffraction analysis showed that its structure is dominated by the β-phase, which is characterized by a maximum dipole moment. It is been shown that the hybrid membranes of the developed sample provide high separation selectivity when desalting an aqueous solution of sodium chloride with a concentration of 26.5 g/l by membrane distillation. The salt rejection coefficient for membranes with a nanofiber layer density from 20.7 ± 0.2 to 27.6 ± 0.2 g/m2 in the studied mode of the membrane distillation process is 99.97−99.98%. It has been established that the use of a highly hydrophobic nanofiber layer with a developed pore structure in combination with a hydrophilic microporous base makes it possible to increase the productivity of the membrane distillation process. The value of the maximum condensate flow through the membranes is on average 7.0 kg m2/h and its depends on the density of the deposited nanofiber layer.

The Temperature-Dependent Monotonic Mechanical Characteristics of Marine Sand–Geomembrane Interfaces

The utilization of geomembrane reinforcement technology is pervasive in marine sand foundation reinforcement projects. However, the elevated temperatures and intricate stress conditions prevalent in marine environments exert a notable influence on the mechanical characteristics of geomembrane interfaces comprising marine sand, which impedes the efficacy of geomembrane reinforcement in marine sand foundations. Nevertheless, there is a lack of research investigating the temperature-dependent interfacial mechanical performance of geomembranes and marine sand under diverse stress states. In this study, a series of monotonic shear tests were carried out on the interface between geomembranes and marine sand within a temperature range of 5 °C to 80 °C. These experiments were carried out using a self-developed large-scale temperature-controlled interfacial dynamic and static shear device. The experimental results demonstrate that temperature has a pronounced effect on the monotonic mechanical characteristics of the geomembrane–marine sand interface, which displays clear temperature dependence. The findings of this study may help in the design and optimization of offshore projects where a marine sand–polymer layer interface exists.

Bench scale Layer-by-Layer microencapasulation of Lactiplantibacillus plantarum WCFS1

Layer-by-Layer (LbL) self-assembly encapsulation is a promising technology for the protection and delivery of lactic acid bacteria. However, laboratory-scale encapsulation is often time-consuming, involves intensive protocols tailored for small-scale operations, requires substantial amounts of energy and water, and results in a low yield of encapsulated biomass. Scaling-up this process to a bench-bioreactor scale is not simply a matter of increasing culture volume as different key parameters (not particularly relevant at lab scale) become critical, including biomass production, the number of polymer layers, and the biomass-to-polymer mass ratio. To our knowledge, this work is the first to address the optimization of each stage of the encapsulation process for Lactiplantibacillus plantarum WCFS1. These stages include biomass production, handling of encapsulation polymers [chitosan (Chi) and alginate (Alg)], critical LbL parameters (e.g., biomass concentration, washing steps). The encapsulation efficiency was assessed by plate-counting microorganisms before and after coating with the polymers layers, followed by spray- and freeze-drying dehydration using fructo-oligosaccharides (FOS) and maltodextrin as carriers. Once dehydrated, microorganisms were either exposed to gastrointestinal conditions or stored for 30 days at 25 and 30 °C. Supplementing culture media with glucose, controlling pH, and harvesting at the early stationary phase during biomass production increased the bacterial recovery after LbL encapsulation (decrease < 1 log unit) compared to bacteria grown under non-controlled conditions (decrease of 4 log units). Coating bacteria (B) with up to two polymer layers (B|Chi or B|Chi|Alg) did not significantly affect bacterial culturability, unlike adding further layers. Zeta-potential measurements enabled the determination of the optimal biomass-to-polymer mass ratio. Using up to a 10:1 bacterial-to-polymer ratio did not change the z-potential for B|Chi or B|Chi|Alg samples. After drying, a synergistic effect between the LbL coating and carrier compounds (FOS and maltodextrin) was observed in terms of culturability. LbL encapsulation mitigated thermal and acidic stresses during spray-drying and gastrointestinal exposure. These findings support scaling-up LbL encapsulation for delivering sensitive lactic acid bacteria strains to the gut.

INVESTIGATION ON THE STRENGTH OF E-GLASS FIBER/AA5052-H32 FIBER METAL LAMINATES CONNECTED USING RIVETED JOINTS

Fiber metal laminates (FMLs) belong to a class of composite materials comprising layers of metal sheets and fiber-reinforced polymers (FRP), configured in a specific sequence. This study investigates the tensile strength of FML specimens joined by riveted joints. FML plates were fabricated using AA5052 aluminium alloy, E-glass fibers, epoxy resin, and layered double hydroxide (LDH) via a hand layup process. The experimental parameters included the pattern of rivets, type of rivet materials, and rivet size. Tensile strength, the output response, was evaluated using Taguchi’s L9 orthogonal array design, followed by testing on a universal testing machine. The main effect plot and 3D surface plots were employed to analyze the tensile test results. Maximum tensile strength was held by the test specimen which was connected by the rivets made up of mild steel. From the ANOVA results presented in Table 6 , it was inferred that the number of rivets used for joining the FML specimens (pattern) played a major role in deciding the tensile strength of the specimens (57.25%). A regression equation, derived from Design Expert software, established the relationship between input variables and the tensile strength of FML specimens. ANOVA was conducted to assess the impact of each process variable on achieving optimal tensile strength. This research contributes novelty by integrating LDH into FML fabrication and demonstrates practical significance through systematic optimization of riveting parameters to enhance tensile strength. Quantitative and qualitative analyses underscore the effectiveness of the proposed FML configuration, validating its potential for structural applications.

Irradiation of hydrophilic acrylic intraocular lenses by a 365 nm UV lamp

Abstract Intraocular lenses (IOLs) based on a transparent hydrophilic acrylic polymer have been irradiated by a 365 nm UV lamp at a 200 mJ/cm2 fluence and at different exposure times, from 1 h up to 19 h, in air and at room temperature. The macromolecular modifications induced in the lens have been investigated by attenuated total reflectance coupled to Fourier transform infrared spectroscopy and optical spectroscopy. Particular attention was devoted to the study of chemical modifications of the IOL by UV irradiation, which induced chain scissions, radical formation, and cross-links in the more superficial polymer layers. The experimental results at long exposures demonstrate that the IOL transmission decreases in the UV and NIR ranges, remaining nearly constant in the visible range.

Toward Sustainable 3D-Printed Sensor: Green Fabrication of CNT-Enhanced PLA Nanocomposite via Solution Casting

The current study explores, for the first time, an eco-friendly solution casting method using a green solvent, ethyl acetate, to prepare feedstock/filaments from polylactic acid (PLA) biopolymer reinforced with carbon nanotubes (CNTs), followed by 3D printing and surface activation for biosensing applications. Comprehensive measurements of thermal, electrical, rheological, microstructural, and mechanical properties of developed feedstock and 3D-printed parts were performed and analyzed. Herein, adding 2 wt.% CNTs to the PLA matrix marked the electrical percolation, achieving conductivity of 8.3 × 10−3 S.m−1, thanks to the uniform distribution of CNTs within the PLA matrix facilitated by the solution casting method. Rheological assessments paralleled these findings; the addition of 2 wt.% CNTs transitioned the nanocomposite from liquid-like to a solid-like behavior with a percolated network structure, significantly elevating rheological properties compared to the composite with 1 wt.% CNTs. Mechanical evaluations of the printed samples revealed improvement in tensile strength and modulus compared to virgin PLA by a uniform distribution of 2 wt.% CNTs into PLA, with an increase of 14.5% and 10.3%, respectively. To further enhance the electrical conductivity and sensing capabilities of the developed samples, an electrochemical surface activation treatment was applied to as-printed nanocomposite samples. The field-emission scanning electron microscopy (FE-SEM) analysis confirmed that this surface activation effectively exposed the CNTs to the surface of 3D-printed parts by removing a thin layer of polymer from the surface, thereby optimizing the composite’s electroconductivity performance. The findings of this study underscore the potential of the proposed eco-friendly method in developing advanced 3D-printed bio-nanocomposites based on carbon nanotubes and biopolymers, using a green solution casting and cost-effective material extrusion 3D-printing method, for electrochemical-sensing applications.

End-to-End Pierced Carbon Nanosheets with Meso-Holes.

The remarkable properties of 2D nanomaterials are well known. However, their high interfacial adhesion energy often leads to restacking issues, limiting their potential in various applications. A strategic synthetic approach is presented to overcome this challenge. Specifically, the study first demonstrates the use of layered aluminosilicate as a sacrificial 2D template to allow the growth of highly ordered meso-holey polymeric layers, which can be subsequently exfoliated upon the removal of aluminosilicate and thermally converted to perpendicularly open meso-holey carbon (POMC). On the other hand, perpendicularly blocked meso-holey carbon (PBMC) is obtained with non-sacrificial 2D template of graphene oxide. When both POMC and PBMC are evaluated by operando hydrodynamic electrochemical impedance spectroscopy and transmission line model analysis for electrochemical reduction of oxygen, POMC achieves a remarkable improvement of charge transfer and mass transfer by up to 4.1 and 7.9 times, respectively, as compared to PBMC. This study therefore highlights the importance of perpendicularly open 2D nanoarchitectures in circumventing the restacking effect, offering valuable insights for leveraging 2D nanomaterials with open meso-holes in various applications.

Regulatory mechanism of blending additives on interface interaction and phase separation of the heterogeneous braid-reinforced hollow fiber membranes

The exfoliation of the polymer layer from the reinforcement material is the key challenge for applying braid-reinforced hollow fiber membranes (BR HFMs). In this work, a mixed amphiphilic additive system was constructed and adopted in BR HFMs preparation by non-solvent induced phase separation (NIPS). The effect of the mixed system on the state of the casting solution and phase inversion process, the interaction between the casting solution and the braid material, together with the structure and filtration performance was studied. The role of the mixed system on the interface coordination and membrane structure formation mechanisms was elucidated. The results showed that both the composition of the mixed amphiphilic additives and the interaction time between the casting solution and braid material threw much light on the interface coordination and membrane formation. The interfacial compatibility of the casting solution and braid material was obviously improved, resulting in the enhancement of the binding force between the braid and PVDF membrane layer. The permeation flux and anti-exfoliation performance were simultaneously improved with the proper addition of the mixed amphiphilic additives. The stability of the BR HFMs was primarily testified by filtration of real sludge suspension solution with back-washing operation.

Polymeric Iodine Transport Layer Enabled High Areal Capacity Dual Plating Zinc‐Iodine Battery

Iodine cathode in aqueous battery has drawn great attention due to its high energy density and high safety. However, iodine has extremely low conductivity of 1×10‐7 S cm‐1, which usually results in low specific capacity. In this work, a PVA‐hydrogel layer was designed to enhance the areal capacity of zinc‐iodine cell. The areal capacity of PVA‐hydrogel layer modified CNT cathode showed twice as higher capacity than that of pure CNT film in a dual‐plating cell, The significant enhancement of the capacity was attributed to the fast iodine transport in the PVA‐hydrogel layer. Besides, the strong interaction between PVA chain and polyiodide anions prevented the shuttle effect. The PVA modified CNT cathode could stably operate for over 3000 hours with remarkably higher capacity and cycle life. We analyzed the uniquely fast transport behavior of polyiodides in PVA hydrogel by in‐situ Raman spectroscopy, in‐situ optical micrography, as well as DFT calculations. It was found that the strong binding force together with lower dissociation energy of iodine on PVA chain is the dominate reason for reduced shuttle effect and fast polyiodide transport. As a result, the assembled PVA‐I2 pouch cells showed excellent performance in both dual‐plating cells and conventional‐type cells.

Polymeric Iodine Transport Layer Enabled High Areal Capacity Dual Plating Zinc-Iodine Battery.

Iodine cathode in aqueous battery has drawn great attention due to its high energy density and high safety. However, iodine has extremely low conductivity of 1×10-7 S cm-1, which usually results in low specific capacity. In this work, a PVA-hydrogel layer was designed to enhance the areal capacity of zinc-iodine cell. The areal capacity of PVA-hydrogel layer modified CNT cathode showed twice as higher capacity than that of pure CNT film in a dual-plating cell, The significant enhancement of the capacity was attributed to the fast iodine transport in the PVA-hydrogel layer. Besides, the strong interaction between PVA chain and polyiodide anions prevented the shuttle effect. The PVA modified CNT cathode could stably operate for over 3000 hours with remarkably higher capacity and cycle life. We analyzed the uniquely fast transport behavior of polyiodides in PVA hydrogel by in-situ Raman spectroscopy, in-situ optical micrography, as well as DFT calculations. It was found that the strong binding force together with lower dissociation energy of iodine on PVA chain is the dominate reason for reduced shuttle effect and fast polyiodide transport. As a result, the assembled PVA-I2 pouch cells showed excellent performance in both dual-plating cells and conventional-type cells.

Construction and performance study of interface layer of carbon fiber/epoxy composites by electrostatic adsorption

AbstractElectrostatic adsorption was used to self‐assemble layers of polymers and nanoparticles with varying charges onto the carbon fiber (CF) surface. This process created two distinct ionic crosslinked network layers: (3‐aminopropyl) triethoxysilane‐phytic acid‐polyethyleneimine (APTES‐PA‐PEI) and (3‐aminopropyl) triethoxysilane‐phytic acid‐nano‐silica (APTES‐PA‐SiO2). Fourier transform infrared spectrophotometer (FTIR) and X‐ray photoelectron spectroscopy (XPS) were used to confirm the presence of ionic interactions. The modified carbon fibers (CFs) exhibited increased surface roughness, higher concentration of functional groups, and improved wettability. Compared to untreated CF composites, the interfacial shear strength (IFSS) and the transverse tensile strength test (TFBT) of CF‐APTES‐PA‐PEI/epoxy composites increased by 67.8% and 62%, respectively. In contrast, the IFSS and TFBT of CF‐APTES‐PA‐SiO2/epoxy composites increased by 63.3% and 52.8%, respectively. The observed strengthening is attributed to the combined effects of ionic crosslinked networks, covalent and hydrogen bonding interactions, enhanced wettability, and the relatively roughened fiber surface. The interfacial layer design approach proposed in this study is both straightforward and effective, demonstrating significant potential for functionalizing CFs. This method is expected to be adaptable for other high‐performance fibers.Highlights The ionic cross‐linked network interface layers were designed. IFSS and TFBT were significantly improved. The enhancement mechanism was elaborated.

Advancing Human–Machine Interface (HMI) through Development of a Conductive‐Textile Based Capacitive Sensor

AbstractSmart wearable sensors in human–machine interfaces (HMI) facilitate communication and interface between humans and robots, as well as among humans. Conventional wearables face significant limitations, including performance degradation under various deformations (e.g., strain and pressure), limited stretchability and flexibility, poor comfort, and breathability, complicating their integration into HMI applications. In response to these limitations, a smart, sewable, high‐precision HMI device based on a soft, textile‐based sensor with machine learning (ML)‐assisted data processing is proposed. The (Ag)‐based fabric electrode integrated into polymeric composite dielectric layer, exhibiting hysteresis error of (≤4%), a tensile strain sensitivity of gauge factor (GF) ≃ 1.03 at 100% elongation, a pressure sensitivity of ≈1.583 × 10−2 kPa−1 at pressures (&lt;50 kPa) and excellent stability (&gt;1000 cycles). To demonstrate its versatility in HMI, the textile‐based sensor is integrated into a glove for real‐time control of a commercially available prosthetic hand and a drone, as well as for sign language recognition, achieving 95.4% classification accuracy using the random forest (RF) classifier across 10 gestures. Beyond gesture recognition, the sensor measures a range of subtle physiological activities (&gt;0.35 kPa), functioning as a force myograph, esophageal manometry, and in gait analysis, among other strain and pressure‐related applications, highlighting exceptional capabilities for advanced wearable systems.

Fabrication of covalently modified graphene oxide-based assembled polymer brushes as efficient aqueous lubricant additive

The present study demonstrates a facile and multistep chemical approach for preparing covalent functionalized graphene oxide (GO) followed by the layer-by-layer assembly of polymer brushes on functionalized GO for aqueous lubricants. Simultaneous reduction and surface modification of GO with 6-amino-4-hydroxy-2-naphthalenesulfonic acid (ANS) and polyethylenimine (PEI) was performed to synthesize functionalized GO (rGO-ANS and rGO-PEI) through a nucleophilic addition reaction pathway to enhance the thermal and dispersion stability in water. Polymer brush particles were fabricated on modified rGO-PEI using anionic polyelectrolytes to extend the load-bearing ability under water-lubricated conditions. The chemical, structural, wettability, and morphological features of functionalized GO and polymer brush particles were well characterized using standard spectroscopic and microscopic techniques. The macrotribological results showed that rGO-ANS (0.5 wt%) exhibited a steady coefficient of friction (COF) with increasing load-bearing ability up to 500 N load (Pm ∼ 4.8 GPa) compared to GO. Although the ANS chains helped to generate an antifrictional tribofilms, the smeared particle film was unable to decrease the COF and wear with increasing the contact pressure to a lower level. Whereas, the poly(sodium 4-styrenesulfonate) (PSS) containing polymer brush (rGO-PBS) showed a significant reduction of the COF (∼ 61.5 %) and wear volume (∼ 82.9 %) at a 147 N load compared to the GO under water lubricated conditions. rGO-PBS also exhibited higher load-bearing capacity up to 800 N load (Pm ∼ 5.8 GPa) with a significantly lower COF and wear among particles. The sulfonate groups containing PSS in rGO-PBS provided robust interfacial adhesive properties to the steel tribo pairs, which facilitated the formation of antifrictional protective tribofilm through well-hydrated polymeric cushioning layers to reduce the COF, wear, and enhance the load-affording ability. Therefore, the excellent dispersibility in water, strong adhesion properties, intrinsic low frictional properties, and strong load-bearing ability make rGO-PBS a potential candidate for aqueous lubricants.

Coupling effects of carbon fibers on the electrification and wear performance of sliding mode triboelectric nanogenerators

This paper introduces carbon fibers into STENG, and investigates the coupling effects of carbon fibers on electrification and wear performance through electrification-wear coupling models and electrification-wear synchronous tests. It is shown that compared to STENG without carbon fibers, STENG with 0.2 wt% carbon fibers exhibits a 90.36 % increase in voltage and a 26.73 % decrease in wear rate. Carbon fibers increase the voltage through increasing the capacitance of the polymer layer, and reduce the transfer film coverage and thus the voltage reduction induced by transfer films. Meanwhile, carbon fibers increase the hardness of the polymer layer and thus reduce plowing and pitting. Although the increase of electrostatic force caused by carbon fibers aggravates wear, the aggravation is slight and can be ignored.

A novel polydopamine-coated bacterial cellulose/g-C3N4 membrane for highly efficient photocatalytic degradation of methylene blue

Photocatalytic oxidation emerges as an eco-friendly approach for chemically degrading water-borne organic pollutants. Establishing a more sustainable process for synthesizing photocatalyst membranes with higher efficiency and reusability is crucial for advancing safe water remediation solutions. In this study, we present a novel photocatalytic membrane incorporating bacterial cellulose (BC), a naturally occurring biopolymer with an intricate fibrous network, and graphitic carbon nitride (g-C3N4), a visible light-responsive non-metal photocatalyst. The composite membrane is augmented with a coating of polydopamine (PDA), an amorphous polymeric layer derived from dopamine to enhance light absorption and reduce photoexcited charge recombination. The BC/g-C3N4/PDA membrane demonstrates a substantial improvement in methylene blue removal efficiency, up to 95.39 % within 150 min of irradiation. Moreover, the PDA-modified membrane exhibits noteworthy recyclability, retaining significant photodegradation ability for up to three cycles. This method offers an accessible and scalable approach to fabricating a highly effective photocatalyst composite membrane suitable for industrial applications.

Interface engineering of electron-ion dual transmission channels for ultra-long lifespan quasi-solid zinc-ion batteries

Hydrogel electrolytes have emerged as effective strategies to prolong the lifespan of aqueous zinc ion batteries (AZIBs). However, dendrites and side reactions are still inescapable due to the residual active water and chaotic migration of Zn2+. Herein, a super stable Zn anode is realized through the synergistic effect of interfacial electron-ion dual transmission channels (EIDC) and an intermediate sodium alginate (SA) gel. Specifically, the SA gel can adjust the solvation structure of Zn2+ and weaken the strong bonding of Zn2+ and H2O molecules. The EIDC polymer layer (PEDOT:PSS) is engineered on the SA hydrogel surfaces, in which PSS chains can offer uniform ion transmission channels via the electrostatic interaction between SO3– groups and Zn2+. While another PEDOT chains can provide electron conducting channels through the conjugated π-π bonds to accelerate charge exchange. Benefiting from the synergistic effect of EIDC polymer layer and SA gel, the as-prepared SA/EIDC gel electrolyte achieves a high ionic conductivity of 41 mS cm–1. The Zn//Zn symmetric batteries exhibit a super-long lifespan of 6750 h at 1 mA cm–2 and 1 mAh cm–2 (>9 months), and cycling life of MnO2-Zn full battery surpasses 4000 cycles. This work presents a new perspective on designing hydrogel electrolytes towards ultra-long lifespan ZIBs.

Epithelial Folding Through Local Degradation of an Elastic Basement Membrane Plate

AbstractEpithelia are polarized layers of cells that line the outer and inner surfaces of organs. At the basal side, the epithelial cell layer is supported by a basement membrane, which is a thin polymeric layer of self‐assembled extracellular matrix (ECM) that tightly adheres to the basal cell surface. Proper shaping of epithelial layers is an important prerequisite for the development of healthy organs during the morphogenesis of an organism. Experimental evidence suggests that local degradation of the basement membrane is one of the mechanisms that can drive epithelial folding. However, how folding emerges in the absence of tissue growth remains elusive. Here, we present a coarse‐grained plate theory model of the basement membrane that assumes force balance between i) cell‐transduced active forces and ii) deformation‐induced elastic forces. We verify key assumptions of this model through experiments in the Drosophila wing disc epithelium and demonstrate that the model can explain the emergence of outward epithelial folds upon local plate degradation. The model accounts for local degradation of the basement membrane as a mechanism for the generation of epithelial folds in the absence of epithelial growth.

Molecular level resolution of the crucial differences in the morphologies of non-fullerene acceptor Y derivatives/donor polymer pm6 heterogeneous films

Characterizing the morphologies of non-fullerene acceptors (NFAs)/donor polymer layers with molecular resolution is crucially important for organic solar cells (OSCs), but remains challenging and insufficient currently. Herein, the morphologies of NFA Yn (n = 5–7)/donor polymer PM6 heterogeneous films were revealed with molecular resolution through scanning tunnelling microscopy and analyzed through density functional theory (DFT) calculations. Y6 forms an interdigitated, ladder-like structure with PM6 which is verified as a kinetic product by the DFT calculations. After annealing, the ladder-like structure coexists with the energy-favorable phase separation one. The difference of the forming energy between the phase separation and ladder-like structure in Y7/PM6 and Y5/PM6 is obviously larger than the one in Y6/PM6, therefore, only the phase separation structure was observed before and after annealing in Y7/PM6 and Y5/PM6. Yn (n = 5–7) shows rather different stacking in its neat domain. Y6 forms a face-to-face, dense packing pair with the lateral shift around half of a molecule. Y7 is a dense packing was well, but the stacking is the T type. Y5 forms an exact face-to-face style while its packing is not the dense one. The morphology differences of Yn (n = 5–7)/PM6 films are closely related to the alterations of the ending groups in the backbones of Yn (n = 5–7) molecules. Annealing reduces the surface-occupied ratio of Y5 and Y7 domains but does not change their stacking. The results are very valuable for the accurate morphology characterizations and the researches of related OSCs and optoelectronics.