Strong Mechanical Properties Research Articles

Transparent and Mechanically Robust Janus Nanofiber Membranes for Open Wound Healing and Monitoring.

The electrospun nanofiber membrane has demonstrated great potential for wound management due to its porous structure, large surface area, mechanical strength, and barrier properties. However, there is a need to develop transparent bioactive nanofibers with strong mechanical properties to facilitate the monitoring of the healing process. In this study, we present an electrospinning-based method for creating transparent (∼80-90%), strong (∼11-13 MPa), and Janus nanofiber membranes. The innovative square pattern architecture of the membrane includes a thin hydrophobic polycaprolactone layer on top of a layer of hydrophilic ethylene-vinyl alcohol nanofiber, which enables the absorption of excess biofluid from the wound and exhibits Janus wettability for water. Furthermore, incorporating 5% chitosan into the composition of the nanofibers accelerates the healing process through its antioxidant properties and antimicrobial activity against various bacteria, including drug-resistant strains. The developed membrane also demonstrates skin-repairing function, quick blood clotting (around 145 ± 12 s), and biocompatibility with keratinocyte (≥90%), as well as in vitro quick cell migration (∼24 h). With a tensile strength of 11-13 MPa, the membrane effectively adheres to the knee joint even after running 4 km. These optimal properties of the electrospun nanofiber membrane make it suitable for effective wound management and inspection of the healing process, without the need for frequent dressing changes.

Incorporation of Graphene Oxide as Hole Transport Layer in PTB7:PC71BM/PFN:Br Pure Organic Solar Cells

Organic solar cells (OSCs) are preferred over inorganic solar cells because they are less expensive, lighter, and easier to manufacture. However, the power conversion efficiency of OSCs remains poor. One promising material for OSCs is PTB7:PC71BM, which has high electrical conductivity, solubility in various solvents, and the ability to be deposited over large areas at low temperatures using cost-effective techniques. All photogenerated excitons must split at the interface between the acceptor and donor materials in order to achieve high quantum efficiency. Additionally, all generated charges must subsequently reach their respective electrodes. Due to its strong mechanical, electrical, thermal, and optical properties, graphene oxide (GO) is a great material for the Hole Transport Layer (HTL) in OSCs. In this study, GO was used as the HTL in PTB7:PC71BM organic solar cells and the effect of GO on these OSCs were examined. SCAPA-1D simulation software was used to simulate the organic solar cells. The thickness of absorber layer has been optimised to be 400nm. We found that GO can improve the efficiency of OSCs by facilitating the dissociation of excitons and by improving the charge transport properties of the device. Our findings imply that GO is a potentially useful material for increasing OSC efficiency.

Hofmeister effect driven dynamic-bond cross-linked dialdehyde xylan hydrogels with rapid response and robust mechanical properties for expanding stent

The biomedical field urgently needs for programmable stent materials with nontoxic, autonomous self-healing, injectability, and suitable mechanical strength, especially self-expanding characteristics. However, such materials are still lacking. Herein, based on gelatin and dialdehyde-functionalized xylan, we synthesized 3D-printable, autonomous, self-healing, and mechanically robust hydrogels with a reversible Schiff base crosslink network. The hydrogels exhibited excellent mechanical properties and automatic healing properties at room temperature. The solid mechanical properties originate from the Schiff base, hydrogen bonding interactions, and xylan nanoparticle reinforcement of the polymer networks. As a proof of concept, the Hofmeister effect enabled the hydrogel to contract in highly concentrated salt solutions. In contrast, the same hydrogel expanded and relaxed in dilute salt solutions (quick response within 10 s), showing ionic stimulus-response and excellent shape memory characteristics, which demonstrated that the prepared hydrogel could be used as self-expanding artificial vascular stents. In particular, good biocompatibility was confirmed by cytotoxicity and compatibility tests, and ex vivo arterial experiments further indicated the feasibility of these artificial vascular scaffolds (the expansion force reached 1.51 N). Combined with its ionic stimuli-responsive shape memory ability, the strong mechanical, self-healing, 3D-printable, and biocompatibility properties make this hydrogel a promising material for artificial stents in various biomedical applications.

Durable fluorinated cobalt oxyhydroxide/calcium alginate hydrogels for activating peroxymonosulfate to enable nearly 100% degradation of ciprofloxacin.

Peroxymonosulfate (PMS) activation by solid catalysts for ciprofloxacin (CIP) removal is a promising method for decontaminating wastewater. However, mainstream catalysts suffer from efficiency and durability issues due to mechanical fragility and structural instability. Here, we have developed a durable calcium alginate hydrogel encapsulating fluorinated cobalt oxyhydroxide (FCO/CAH), fabricated by a simple hydrogen-bond-assisted cross-linking reaction, to enhance PMS activation for complete CIP removal. The optimized 2-FCO/CAH could generate abundant singlet oxygen (1O2) and sulfate radicals (SO4˙-) with PMS, resulting in 0.433 min-1 kinetic constant and approximately 100% CIP degradation within 10 minutes. This exceptional degradation efficiency is due to the even distribution of 2-FCO, which maximizes catalytic sites for PMS activation, and the multichannel cavity structure of CAH, which effectively enriches both PMS and CIP. Furthermore, the durability of 2-FCO/CAH was proved by its negligible decay in CIP removal efficiency (∼100%) and good microstructure retention after 6 consecutive cycles, facilitated by a stable surface reconstructed interphase on the 2-FCO surface and the strong mechanical property of 2-FCO/CAH. Our work showcases a facile approach to constructing durable hydrogel catalysts that improve PMS-mediated antibiotic degradation.

Development and Characterization of Fast-Dissolving Tablets to Enhance Bioavailability of BCS Class II Drugs by Solid Dispersion Method

Background: Rapid tablet or capsule dissolution requires the tablet to disintegrate and dissolve at a higher rate, enhancing drug dissolution and bioavailability. Suitable disintegrants have shown an appreciable rate of disintegration or dissolution. Using factorial design for formulation to improve bioavailability is a key focus in pharmaceutical research to enhance dissolution Methods: Azelnidipine (Azp) tablets were formulated with Hydroxypropyl β-cyclodextrin (HβCD), β-cyclodextrin (βCD), and Kolliphor HS15 (HS15) to enhance solubility. A 23 factorial design optimized the formulation, focusing on disintegration time (DT) and time for 90% dissolution (T90). Eight formulations (F1-F8) were prepared using the kneading method. Tablets were evaluated for physical properties, drug content, friability, dissolution, and drugexcipient interactions (FTIR and DSC). The optimal formulation (F9) was determined via desirability analysis. Results: Tablets showed acceptable Carr's index (CI), Hausner ratio (HR), and Angle of Repose (AR). Increasing βCD concentration decreased DT, enhancing water absorption and faster dissolution. βCD tablets had the lowest DT among the formulations, with F4 showing the best disintegration. Higher HS15 concentration also reduced DT, with F8 achieving the highest drug release (T90%) within 60 minutes. R² values ranged from 0.922 to 0.994, indicating high predictability. The optimal formulation had a desirability of 1.0, consisting of 3.523 mg HS15, 28.4 mg βCD, and 1.49 mg βCD, with a DT of 102 ± 1.13 seconds and 98% dissolution. FTIR and DSC confirmed no drug–excipient interactions. Conclusion: Optimized super disintegrant concentrations and wet granulation techniques resulted in tablets with strong mechanical properties, rapid disintegration, and consistent drug content. Future research and in vivo studies should explore additional excipient combinations.

Robust self-healing capacity and high mechanical properties of castor oil-based waterborne polyurethane based on “kill two birds with one stone” strategy

Achieving ideal combination of high self-healing efficiency and good mechanical properties is of significance for the breakthrough in the application of self-healing materials. Herein, the functionalized castor oil-based waterborne polyurethane (DA-CWPU) was constructed based on “killing two birds with one stone” molecular design strategy with the addition of self-healing monomer D-A adduct. Firstly, D-A adduct containing flexible D-A bonds and rigid ring structure was prepared by D-A reaction with furfuryl alcohol (FA) and bismaleimide (BMI) as raw materials, which could not only effectively enhanced the self-healing ability of the material, but also ensured the strong mechanical properties. Then, DA-CWPU emulsion with favourable self-healing and mechanical properties was synthesized by the polymerization of castor oil (CO), isophorone diisocyanate (IPDI) and D-A adduct. The DA-CWPU film has preferable self-healing efficiency (93 % at 100 °C for 50 min), unique shape memory effect (rehabilitate after heating at 100 °C for 45 s), good toughness (485 MJ/m3), strong tensile strength (5.96 MPa) and sufficient elongation (115 %). At the same time, the self-healing DA-CWPU film can be recycled through solution casting. The sustainable castor oil-based waterborne polyurethane can be used as finishing agents for leather products, which realizes repeatedly self-healing in case of surface damage, greatly increasing the service life of the material and mechanical properties, providing a new approach for the development of mechanically robust self-healing materials.

A review of electrical and piezoelectric properties of nanocellulose biocomposites

Abstract The increasing request for lightweight, environmentally sustainable materials with versatile functionality and strong mechanical properties is driving renewed interest in nanocellulose for electrical applications. Nanocellulose, a biologically derived polymeric nanomaterial, has seen significant growth in the global market due to advancements in nanotechnology and the increasing need for sustainable materials. This has accelerated research into the development of cellulose-based nanomaterials. However, nanocellulose on its own does not inherently possess the ability to function as a conductive material. To address this limitation, researchers have explored various modifications, such as combining nanocellulose with conductive materials or applying specific chemical treatments. These approaches have been shown to enhance the electrical conductivity of nanocellulose, making it suitable for use in electrically conductive composites. Over the past few decades, nanocellulose composites have been extensively studied for their applications in energy, electronics, biomedicine, health, and environmental sectors. Nanocellulose possesses a unique combination of exceptional properties, including biodegradability, renewability, and a distinctive fibrous structure, proving that it is the best choice for these uses. The superior electrical properties of nanocellulose-based composites, coupled with their flexibility, ease of production, and biocompatibility, make them highly desirable for various advanced technological applications. Significant advancements have been achieved by researchers in fabricating various types of nanocellulose materials and exploring their potential in nanogenerators, humidity sensors, gas sensors, and supercapacitors. The ability to modify the surface of nanocellulose and its robust properties offer numerous opportunities for creating hybrid materials within the electrical domain.

Fabrication and Properties of Hydrogel Dressings Based on Genipin Crosslinked Chondroitin Sulfate and Chitosan.

Multifunctional hydrogel dressings remain highly sought after for the promotion of skin wound regeneration. In the present study, multifunctional CHS-DA/HACC (CH) hydrogels with an interpenetrated network were constructed using hydroxypropyl trimethyl ammonium chloride modified chitosan (HACC) and dopamine-modified chondroitin sulfate (CHS-DA), using genipin as crosslinker. The synthesis of HACC and CHS-DA was effectively confirmed using Fourier transform infrared (FT-IR) analysis and 1H nuclear magnetic resonance (1H NMR) spectroscopy. The prepared CH hydrogels exhibited a network of interconnected pores within the microstructure. Furthermore, rheological testing demonstrated that CH hydrogels exhibited strong mechanical properties, stability, and injectability. Further characterization investigations showed that the CH hydrogels showed favorable self-healing and self-adhesion properties. It was also shown that increasing HACC concentration ratio was positively correlated with the antibacterial activity of CH hydrogels, as evidenced by their resistance to Escherichia coli and Staphylococcus aureus. Additionally, Cell Counting Kit-8 (CCK-8) tests, fluorescent images, and a cell scratch assay demonstrated that CH hydrogels had good biocompatibility and cell migration ability. The multifunctional interpenetrated network hydrogels were shown to have good antibacterial properties, antioxidant properties, stable storage modulus and loss modulus, injectable properties, self-healing properties, and biocompatibility, highlighting their potential as wound dressings in wound healing applications.

Nacre‐Mimetic Multi‐Mechanical Synergistic Ceramic Aerogels with Interfacial Bridging and Stress Delocalization

AbstractElastic ceramic aerogels are exceptionally suitable for thermal insulating applications, but lacking multi‐mechanical synergistic high strength remains a deficiency. Inspired by the robust protective shells of mollusks in nature, which feature distinct hierarchical ordered structures, exhibiting strong and tough mechanical properties, a system construction and structural governing strategy is proposed to allow the nanostructure to assemble strong and flexible ceramic aerogels. Through the design of a hierarchical multi‐arched structure configurated binary‐soldering‐assemble interfacial topology interlocking, concentrated stress is effectively discrete. This biomimetic strategy enables the effective dissipation of mechanical energy, resulting in ceramic aerogels with exemplary compressive resilience, bendability, tensile resistance, and their strength exceeding that of other nanofibrous aerogels by up to tenfold. Additionally, the flexible aerogels also show remarkable thermal resistance from −196 to 1100 °C and superior thermal insulation capabilities (39.72 mW m−1 K−1), making them more suitable for the applications.

Electrospun "Hard-Soft" Interpenetrating Nanofibrous Tissue Scaffolds Facilitating Enhanced Mechanical Strength and Cell Proliferation.

"Soft" hydrogel-based macroporous scaffolds have been widely used in tissue engineering and drug delivery applications due to their hydrated interfaces and macroporous structures, but have drawbacks related to their weak mechanics and often weak adhesion to cells. In contrast, "hard" poly(caprolactone) (PCL) electrospun fibrous networks have desirable mechanical strength and ductility but offer minimal interfacial hydration and thus limited capacity for cell proliferation. Herein, we demonstrate the fabrication of interpenetrating nanofibrous networks based on coelectrospun PCL and poly(oligoethylene glycol methacrylate) (POEGMA) nanofibers that exhibit the mechanical benefits of PCL but the interfacial hydration benefits of hydrogels. The electrospinning process results in partially aligned but interpenetrating fiber network with minimal internal phase separation, leading to anisotropic but strong mechanical properties even in the hydrated state; apparent ultimate tensile strengths of the swollen scaffolds ranged from 429 ± 39 kPa in the direction of fiber alignment (longitudinal) to 86 ± 25 kPa perpendicular to fiber alignment (cross-longitudinal), typical of PCL-based scaffolds and enabling efficient suture retention in different directions. However, contact angle measurements indicate hydrogel-like interfacial properties due to the presence of the interpenetrating POEGMA network. C2C12 myoblast proliferation in the PCL-POEGMA scaffolds was 50% higher than that observed on PCL-only scaffolds, a result attributed to the presence of the more hydrophilic POEGMA interpenetrating nanofiber network. Overall, this method is demonstrated to represent a facile single-step strategy to fabricate strong macroporous but still interfacially hydrophilic scaffolds for tissue engineering applications.

Composite biopolymer foams fabricated from natural aldehyde functionalized chitosan-whey protein amyloid fibrils: Application for removal of phthalate esters from water

In this work, composite biopolymer foams from chitosan and whey isolate protein amyloid fibrils were prepared for the removal of phthalate esters from water. Natural aldehyde functionalization enhanced the affinity for dibutyl phthalate (DBP), with citral being the most effective. The citral-grafted foams (WCGC) had tunable hydrophobicity, strong mechanical properties, and good water stability. WCGC1.5 foam exhibited a high removal efficiency (96.06 %) of DBP. The adsorption process reached adsorption equilibrium rapidly within 8 h and could be described by pseudo-second-order kinetic and Freundlich isotherm models, indicating a non-homogeneous and chemisorptive sorption process. The maximum adsorption capacity for DBP reached 332.42 mg/g. Moreover, DBP adsorption could be enhanced in alkaline environment and the removal efficiency increased to 98.27 % at pH 10. The removal efficiency of DBP by WCGC1.5 remained above 85 % after the five adsorption-desorption cycles. WCGC1.5 also showed broad-spectrum adsorption behavior, with strong affinity and removal efficiency for six common plasticizers, including DIBP (85.97 %), DPP (91.7 %), DHXP (99.1 %), DEHP (99.09 %), DNOP (91.6 %) and BBP (89.88 %).

Suitability of an ornamental tree, Sorbus alnifolia, as a source of industrial wood: Properties and the juvenile to mature transition

Ornamental trees are being promoted to supplement wood for industrial applications in China. To determine the wood utilization potential of an ornamental tree species, Sorbus alnifolia, this study investigated the radial variation of anatomical characteristics of its wood cross-section. The results showed that S. alnifolia is porous with high cell wall percentage, fiber percentage, and vessel percentage, small fiber and vessel sizes, and low vessel frequency. The transition age between juvenile wood and mature wood is 7 to 11 years for vessels, 12 to 16 years for axial parenchyma, and 18 to 24 years for fibers. Mature wood exhibits a higher percentage of cell walls, thicker fiber walls, and a lower percentage of vessels than juvenile wood. This result implies that wood is easy to dry, has strong permeability, good physical and mechanical properties, and a high fiber yield.

Research on the Configuration of Multi-Component Solid Waste Cementitious Materials and the Strength Characteristics of Consolidated Aeolian Sand

Developing green, low-carbon building materials has become a viable option for managing bulk industrial solid waste. This paper presents a kind of all solid waste cementitious material (SWCM), which is made entirely from six common industrial wastes, including carbide slag and silica fume, that demonstrate strong mechanical properties and effectively stabilize aeolian sand (AS). Initially, we investigated the mechanical strength of waste-based cementitious materials in various mix ratios, focusing on their ability to stabilize river sand (RS) and aeolian sand. The results show that it is necessary to use alkaline solid waste carbide slag to provide a suitable reaction environment to achieve the desired strength. In contrast, the low reactivity of coal gangue powder did not contribute effectively to the strength of the cementitious material. Further orthogonal experiments determined the impact of different waste dosages on the strength of stabilized AS. It was found that increasing the amounts of carbide slag, silica fume, and blast furnace slag powder improved strength, while increasing fly ash first increased and then decreased strength. In contrast, higher additions of desulfurization gypsum and coal gangue powder led to a continuous decrease in strength. The optimized mix is carbide slag—desulfurization gypsum—fly ash—silica fume—blast furnace slag powder in a ratio of 4:2:2:3:3. The experimental results using SWCM to stabilize AS indicated a proportional relationship between strength and SWCM content. When the content is ≥20%, it meets the strength requirements for road subbases. The primary hydration products of stabilized AS are C-(A)-S-H, AFt, and CaCO3. Increasing the SWCM content enhances the reaction degree of the materials, thereby improving mechanical strength. This study highlights the mechanical properties of cementitious materials made entirely from waste for stabilizing AS. It provides a reference for the large-scale utilization of industrial solid waste and practical applications in desert road construction.

Reversible Emission Color, Brightness, and Shape Changes of AIEgen‐containing Bulk Polymers

AbstractBulk polymers generally exhibit faster response, higher shape‐deformation speed, and stronger mechanical properties than the hydrogels. However, it still remains a formidable challenge to enable bulk polymers to exhibit reversible changes in shape and fluorescence simultaneously. Herein, for the first time, the temperature‐responsive reversible changes in fluorescence color, brightness, and shape of semi‐crystalline poly(ε‐caprolactone) (PCL) network doped with a D‐A based aggregation‐induced emission luminogen (AIEgen) is realized. The fabricated flower‐like and dragonfly‐shaped actuators show reversible blooming‐closing and wing fanning behaviors, respectively, as well as reversible fluorescence‐changing effects. Notably, the response and shape‐deformation speed as well as mechanical properties of the system is much better than the reported hydrogels. Moreover, a smart switch is developed to demonstrate the potential applications. The stick fabricated by the sample can lift and release an object 1000 times larger than its weight, serving as a color‐changing artificial muscle. This material design strategy may shine light on the design and preparation of other reversible shape‐deformation polymers in combination with stimuli‐responsive luminescence‐changing AIEgens, such as mechanochromic, thermochromic, and photochromic luminogens.

Enhanced Water Resistance of TiO2-GO-SMS-Modified Soil Composite for Use as a Repair Material in Earthen Sites.

Most earthen sites are located in open environments eroded by wind and rain, resulting in spalling and cracking caused by shrinkage due to constant water absorption and loss. Together, these issues seriously affect the stability of such sites. Gypsum-lime-modified soil offers relatively strong mechanical properties but poor water resistance. If such soil becomes damp or immersed in water, its strength is significantly reduced, making it unviable for use as a material in the preparation of earthen sites. In this study, we achieved the composite addition of a certain amount of sodium methyl silicate (SMS), titanium dioxide (TiO2), and graphene oxide (GO) into gypsum-lime-modified soil and analyzed the microstructural evolution of the composite-modified soil using characterization methods such as XRD, SEM, and EDS. A comparative study was conducted on changes in the mechanical properties of the composite-modified soil and original soil before and after immersion using water erosion, unconfined compression (UCS), and unconsolidated undrained (UU) triaxial compression tests. These analyses revealed the micro-mechanisms for improving the waterproof performance of the composite-modified soil. The results showed that the addition of SMS, TiO2, and GO did not change the crystal structure or composition of the original soil. In addition, TiO2 and GO were evenly distributed between the modified soil particles, playing a positive role in filling and stabilizing the structure of the modified soil. After being immersed in water for one hour, the original soil experienced structural instability leading to collapse. While the water absorption rate of the composite-modified soil was only 0.84%, its unconfined compressive strength was 4.88 MPa (the strength retention rate before and after immersion was as high as 93.1%), and the shear strength was 614 kPa (the strength retention rate before and after immersion was as high as 96.7%).

High-Performance Wearable Joule Heater Derived from Sea-Island Microfiber Nonwoven Fabric.

A three-dimensional (3D) hierarchical microfiber bundle-based scaffold integrated with silver nanowires (AgNWs) and porous polyurethane (PU) was designed for the Joule heater via a facile dip-coating method. The interconnected micrometer-sized voids and unique hierarchical structure benefit uniform AgNWs anchored and the formation of a high-efficiency 3D conductive network. As expected, this composite exhibits a superior electrical conductivity of 1586.4 S/m and the best electrothermal conversion performance of 118.6 °C at 2.0 V compared to reported wearable Joule heaters to date. Moreover, the durable microfiber bundle-PU network provides strong mechanical properties, allowing for the stable and durable electrothermal performance of such a composite to resist twisting, bending, abrasion, and washing. Application studies show that this kind of Joule heater is suitable for a wide range of applications, such as seat heating, a heating jacket, personal thermal management, etc.

Double Network Gel Electrolyte with High Ionic Conductivity and Mechanical Strength for Zinc-Ion Batteries.

Gel electrolytes hold promise for stabilizing zinc-ion batteries (ZIBs), but achieving both high ionic conductivity and strong mechanical properties remains challenging. This work presents a double network gel electrolyte based on poly(N-hydroxymethyl acrylamide) (PNMA) and sodium alginate (SA), overcoming this trade-off. The PNMA network provides mechanical strength and water retention, while the SA network facilitates rapid zinc-ion (Zn2+) diffusion through tailored solvation. This double network gel exhibits a tensile strength of up to 838 kPa, significantly higher than previous reports. The SA network provides ion channels for rapid transport of hydrated Zn2+, enhancing the ionic conductivity to a ground-breaking 33.1 mS cm-1. This value is even higher than the liquid electrolytes. The growth of Zn dendrites is also suppressed due to the mechanical constraint and rapid ion conduction. In symmetrical cells, the PNMA/SA gel demonstrates exceptional cycling stability (>2000 h). Characterizations show this is because of reduced free water amount, hindering cathode material dissolution. The full cells with sodium vanadate cathode manifest a high capacity (364.8 mA h g-1 at 0.5 A g-1) and excellent capacity retention (83% after 2500 cycles at 10 A g-1). This double network design offers a way to achieve high-performance and stable ZIBs.

Long-term storage and intradermal vaccination of tumor-derived exosomes via sugar microneedles for improving tumor immunotherapies

Tumor-derived exosomes are gaining recognition as a promising cancer vaccine for immunotherapies due to their abundant tumor antigens and their role as endogenous carriers for antigen delivery. However, challenges including unstable membrane structures and compromised protein integrity during long-term storage, as well as the absence of effective delivery methods, restrict their clinical applications. Herein, we introduce an exosomes-loaded sugar microneedle (EXO-SMN) patch that not only allows for the long-term storage of exosomes but also facilitates intradermal delivery to enhance immunotherapies. By employing a two-casting micro-molding method, the EXO-SMN patch is composed of an array of tips simply made from trehalose, with a polyvinylpyrrolidone backing. The EXO-SMN patch demonstrates the capability to effectively protect the loaded exosomes, maintaining their membrane structure and protein integrity even after being stored at room temperature for at least one month. Additionally, the EXO-SMN patch possesses strong mechanical properties for skin penetration, facilitating the rapid release of exosomes into the skin within 120 s, and prolonging exosome retention in both skin and lymph nodes compared to intravenous (IV) or subcutaneous (SC) injections. Intradermal vaccination of tumor-derived exosomes via the EXO-SMN patch elicited higher antigen-specific immune responses and resulted in slower tumor growth compared to IV or SC injection. Given its easy to use and reliability, the proposed EXO-SMN patch could eventually facilitate the storage and delivery of exosomes in various biomedical applications.

Surface engineered covalent bridging strategy to in-situ fabricate MXene-based core-sheath fiber for flexible supercapacitors with ultrahigh volumetric energy density and mechanical properties

MXene fiber-based supercapacitors (SCs) are expected to make a major contribution to the ongoing development of wearable electronics and metaverse technologies in future. However, to fabricate fiber electrodes with high energy density and strong mechanical properties remains a major challenge for their usage in SCs. Herein, we fabricated a flexible core-sheath structural Ti3C2Tx MXene@polyaniline (MX@PA) fiber electrode with ultrahigh volumetric energy density and good tensile strength through surface engineered covalent bridging strategy via wet spinning and in situ oxidant-freepolymerization processes. Benefiting from the high-order core-sheath structure and strong Ti-O-N covalent bonds between MXene and PANI, an ultrahigh tensile strength (∼168.1 MPa) and super-toughed (∼1.75 MJ cm−3) fiber electrode was achieved. The assembled SC provided much higher volumetric capacitance of 631F cm−3 (based on the SC device) at a current density of 0.5 A cm−3 and ultralong-term cycling stability with 92.6 % capacitance retention after 10000 cycles due to the rapid electron conduction of core (MXene) and large pseudocapacitive charge transfer of the sheath (PANI). As a result, the SC delivers excellent volumetric energy density of 56.1 mWh cm−3 at a power density of 204.9 mW cm−3. The integrated SC found actual application to power a 2.5 V red LED.

Advancements in Polyethylene Oxide (PEO)-Active Filler Composite Polymer Electrolytes for Lithium-Ion Batteries: A Comprehensive Review and Prospects.

Polyethylene oxide (PEO) has become a highly sought-after polymer electrolyte for lithium-ion batteries (LIBs) due to its high ionic conductivity, strong mechanical properties, and broad electrochemical stability range. However, its usefulness is hindered by its limited ionic conductivity at typical temperatures (<60 °C). Many researchers have delved into the integration of active fillers into the PEO matrix to improve the ionic conductivity and overall efficiency of composite polymer electrolytes (CPEs) for LIBs. This review delves deeply into the latest developments and insights in CPEs for LIBs, focusing on the role of PEO-active filler composites. It explores the impact of different types and morphologies of active fillers on the electrochemical behavior of CPEs. Additionally, it explores the mechanisms that contribute to the improved ionic conductivity and Li-ion transport in PEO-based CPEs. This paper also emphasizes the present obstacles and prospects in the advancement of CPEs containing PEO-active filler composites for LIBs. It serves as a valuable reference for scientists and engineers engaged in the domain of advanced energy storage systems, offering insights for the forthcoming development and enhancement of CPEs to achieve superior performance in LIBs.