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The lack of acid-proof high-potential cathode largely limits the development and competitiveness of proton batteries. Herein, the authors systematically investigated six dihydroxynaphthalenes (DHNs) and found that 2,6-DHN delivered the best cathode performance in proton battery with the highest redox potential (0.84 V, vs SHE) and a specific capacity of 91.6 mAh g-1 at 1 A g-1 . In situ solid-state electropolymerization of DHNs is responsible for the voltage and capacity fading of DHNs, and 2,6-DHN's excellent electrochemical performance is derived from its high polymerization energy barrier. By compounding with rGO, the 2,6-DHN/rGO electrode can maintain a specific capacity of 89 mAh g-1 even after 12â¯000 cycles at 5 A g-1 . When it is paired with the 2,6-dihydroxyanthraquinone (DHAQ) anode, the assembled rocking-chair all-organic proton battery exhibited a high cell voltage of 0.85 V, and excellent energy/power densities (70.8 Wh kg-1 /850 W kg-1 ). This study showcases a new-type high-potential proton-containing organic cathode and paves the way for constructing a high-voltage rocking-chair proton battery. Also, in situ solid-state electropolymerization will inspire the further study of phenol-based small-molecule electrodes.
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Despite incorporation of organic groups into silica-based aerogels to enhance their mechanical flexibility, the wide temperature reliability of the modified silicone aerogel is inevitably degraded. Therefore, facile synthesis of soft silicone aerogels with wide-temperature stability remains challenging. Herein, novel silicone aerogels containing a high content of Si are reported by using polydimethylvinylsiloxane (PDMVS), a hydrosilylation adduct with water-repellent groups, as a "flexible chain segment" embedded within the aerogel network. The poly(2-dimethoxymethylsilyl)ethylmethylvinylsiloxane (PDEMSEMVS) aerogel is fabricated through a cost-effective ambient temperature/pressure drying process. The optimized aerogel exhibits exceptional performance, such as ultra-low density (50 mg cm-3), wide-temperature mechanical flexibility, and super-hydrophobicity, in comparison to the previous polysiloxane aerogels. A significant reduction in the density of these aerogels is achieved while maintaining a high crosslinking density by synthesizing gel networks with well-defined macromolecules through hydrolytic polycondensation crosslinking of PDEMSEMVS. Notably, the pore/nanoparticle size of aerogels can be fine-tuned by optimizing the gel solvent type. The as-prepared silicone aerogels demonstrate selective absorption, efficient oil-water separation, and excellent thermal insulation properties, showing promising applications in oil/water separation and thermal protection.
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With the advantages of lightweight and low thermal conductivity properties, polymeric foams are widely employed as thermal insulation materials for energy-saving buildings but suffer from inherent flammability. Flame-retardant coatings hold great promise for improving the fire safety of these foams without deteriorating the mechanical-physical properties of the foam. In this work, four kinds of sulfur-based flame-retardant copolymers are synthesized via a facile radical copolymerization. The sulfur-containing monomers serve as flame-retardant agents including vinyl sulfonic acid sodium (SPS), ethylene sulfonic acid sodium (VS), and sodium p-styrene sulfonate (VSS). Additionally, 2-hydroxyethyl acrylate (HEA) and 4-hydroxybutyl acrylate are employed to enable a strong interface adhesion with polymeric foams through interfacial H-bonding. By using as-synthesized waterborne flame-retardant polymeric coating with a thickness of 600 µm, the coated polyurethane foam (PUF) can achieve a desired V-0 rating during the vertical burning test with a high limiting oxygen index (LOI) of >31.5 vol%. By comparing these sulfur-containing polymeric fire-retardant coatings, poly(VS-co-HEA) coated PUF demonstrates the best interface adhesion capability and flame-retardant performance, with the lowest peak heat release rate of 166 kW m-2 and the highest LOI of 36.4 vol%. This work provides new avenues for the design and performance optimization of advanced fire-retardant polymeric coatings.
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Retardadores de Chama , Polímeros , Poliuretanos , Enxofre , Poliuretanos/química , Polímeros/química , Enxofre/química , Retardadores de Chama/análise , IncêndiosRESUMO
Carbon nanofiber (CNF)-based supercapacitors have promising applications in the field of energy storage. It is desirable, but remains challenging, to develop CNF electrode materials with large specific surface area (SSA), high specific capacitance (SC), and high power density, as well as excellent cycling stability and high reliability. Herein, acrylonitrile-acrylic acid copolymer P(AN-co-AA) was synthesized for the preparation of nitrogen-doped microporous CNFs. Thermal degradation of the AA segment leads to the formation of micropores that are distributed not only on the CNF surface, but also inside the material. The microporous structure and nitrogen content can be manipulated at the molecular level by adjusting the weight ratio between AN and AA, and the SSA and SC could reach as high as 1099â m2 g-1 and 156â F g-1 , respectively. After KOH activation, the activated CNFs have an extremely high SSA of 2117â m2 g-1 and SC of 320â F g-1 , which are among the highest values ever reported for electric double-layer supercapacitors with an alkaline electrolyte. Furthermore, the capacitance retention, which can be maintained at 99 % even after 16 000 cyclic tests, reveals outstanding durability and repeatability.
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State-of-the-art human detection methods focus on deep network architectures to achieve higher recognition performance, at the expense of huge computation. However, computational efficiency and real-time performance are also important evaluation indicators. This paper presents a fast real-time human detection and flow estimation method using depth images captured by a top-view TOF camera. The proposed algorithm mainly consists of head detection based on local pooling and searching, classification refinement based on human morphological features, and tracking assignment filter based on dynamic multi-dimensional feature. A depth image dataset record with more than 10k entries and departure events with detailed human location annotations is established. Taking full advantage of the distance information implied in the depth image, we achieve high-accuracy human detection and people counting with accuracy of 97.73% and significantly reduce the running time. Experiments demonstrate that our algorithm can run at 23.10 ms per frame on a CPU platform. In addition, the proposed robust approach is effective in complex situations such as fast walking, occlusion, crowded scenes, etc.
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Imageamento Tridimensional/métodos , Monitorização Fisiológica/métodos , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Inteligência Artificial , Cabeça/fisiologia , Humanos , Fenômenos FísicosRESUMO
The single whey acidic protein (WAP) domain (SWD)-containing proteins, also called type III crustins, are a group of antimicrobial peptides (AMPs) in crustaceans. At present, a number of SWDs have been identified in shrimp, which showed essential antibacterial activities. However, the roles of SWDs in antiviral immune responses have not been reported up to now. In this study, a novel SWD (LvSWD3) was identified from Pacific white shrimp, Litopenaeus vannamei, which contained a typical single WAP domain homologous to those of other crustacean SWDs. Although lacking the pro and arg-rich region between the signal peptide and the WAP domain, LvSWD3 was closely clustered with other shrimp SWDs in the phylogenetic tree. Similar to many shrimp SWDs, the highest expression of LvSWD3 was detected in hemocytes. The LvSWD3 expression exhibited only limited changes after challenges with Vibrio parahaemolyticus, Poly (I:C) and lipopolysaccharide, but was significantly up-regulated after white spot syndrome virus (WSSV) infection. Silencing of LvSWDs significantly accelerated the death of the WSSV-infected but not the V. parahaemolyticus-infected shrimp. The recombinant LvSWD3 protein did not show proteinase inhibitory and antibacterial activities but could significantly postpone the death of WSSV-infected shrimp and reduce the viral load in tissues. These suggested that LvSWD3 was a novel SWD with antiviral activity.
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Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Regulação da Expressão Gênica/imunologia , Penaeidae/genética , Penaeidae/imunologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Sequência de Bases , Lipopolissacarídeos/farmacologia , Filogenia , Poli I-C/farmacologia , Alinhamento de Sequência , Regulação para Cima/imunologia , Vibrio parahaemolyticus/fisiologiaRESUMO
Cyanobacteria are ubiquitously distributed in water on the Earth. It has long been known that the cyanobacterial bloom in aquaculture ponds can cause acute and massive deaths of shrimp. However, the long-term and chronic effects of the cyanobacterial bloom on shrimp are still poorly understood. In this study, the immune state of white pacific shrimp, Litopenaeus vannamei, surviving a naturally occurring cyanobacterial bloom was investigated and tracked for 70 d. Compared with the control, the growth of shrimp suffering high concentrations of cyanobacteria was obviously postponed. In these shrimp, the activities of the NF-κB, JAK/STAT and P38 MAPK immune signaling pathways and the expression of many antimicrobial peptide genes were down-regulated, whereas the expression of C-type lectins was significantly up-regulated. Although the mRNA level of lysozyme was reduced, the expression of the invertebrate-type lysozyme gene was increased. Furthermore, the concentration of hemocytes in hemolymph was greatly decreased, but the phagocytic activity of hemocytes was increased. These suggested that the cyanobacterial bloom has significant and complex influences on the immune system of shrimp, and in turn, alteration of the immune state could be a factor by which few shrimp can survive the cyanobacterial bloom. Thus, the current study could help further understand the interactions between the aquaculture water environment and the immune system of shrimp.
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Proteínas de Artrópodes/genética , Cianobactérias/fisiologia , Eutrofização , Regulação da Expressão Gênica , Imunidade Inata , Penaeidae/imunologia , Animais , Proteínas de Artrópodes/metabolismo , Hemócitos/metabolismo , Hemócitos/microbiologia , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Penaeidae/genética , Penaeidae/microbiologia , Fagocitose , Transdução de SinaisRESUMO
Fatty acid synthase (FAS) is an important enzyme that catalyzes the synthesis of fatty acids. In this study, the role of the FAS gene from pacific white shrimp Litopenaeus vannamei (LvFAS) in immune responses against Vibrio parahaemolyticus infection was studied. The expression of LvFAS could be up-regulated upon infection of V. parahaemolyticus and stimulation of lipopolysaccharide and poly (I:C). The promoter of LvFAS was predicted to harbor a NF-κB binding site and dual-luciferase reporter assays demonstrated that the NF-κB family proteins Relish, sRelish and Dorsal could activate the transcription of LvFAS. After knockdown of LvFAS expression using RNAi strategy, both the mortality of V. parahaemolyticus infected shrimps and the bacterial load in shrimp tissues were significantly increased. Meanwhile, the expression of many immune-responsive genes, such as antimicrobial peptides, C-type lectins (CTLs), lysozyme and hemolin, was down-regulated. These suggested that LvFAS could play a positive role in anti-V. parahaemolyticus responses in shrimp. To our knowledge, this is the first study that investigates the role of FAS in antibacterial immunity in animals, which may indicate the relationship between the anabolism of fatty acids and immune responses in crustaceans.
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Proteínas de Artrópodes/genética , Ácido Graxo Sintases/genética , Penaeidae/genética , Penaeidae/imunologia , Vibrio parahaemolyticus/fisiologia , Animais , Proteínas de Artrópodes/metabolismo , Sequência de Bases , Ácido Graxo Sintases/metabolismo , Penaeidae/microbiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Electrically conductive fiberfibre/fabric composites (ECFCs) are competitive candidates for use in wearable electronics. Therefore, it is essential to develop mechanically robust ECFC strain sensors with sensing performance. In this study, MXene assembly and hot-pressing were combined to prepare strong yet breathable ECFCs for strain and temperature sensing. Hydrogen bonding between MXene and polyurethane (PU) and ultrasonication-induced interfacial sintering were responsible for MXene nanosheets assembly on the PU nanofibers. MXene decoration made PU nanofibers electrically conductive, resulting in a conductive network. Hot-pressing improved interface adhesion among the conductive nanofibers. Thus, the mechanical properties of the nanofiber composites, including tensile strength, toughness and fracture energy, were enhanced. The nanofiber composites exhibited surface stability and durability. When the nanofiber composites were used as strain sensors, they showed breathability with a linear resistance response ranging from 1 % to 100 % and cycling stability. In addition, they produced stable sensing signals over 1000 cycles when a notch was present. They could also monitor temperature variations with a negative temperature coefficient (-0.146 %/°C). This study provides an interfacial regulation method for the preparation of multi-functional nanofiber composites with potential applications in flexible and wearable electronics.
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Solar-driven interfacial evaporation (SDIE) is a green and sustainable technique for desalination. Hydrogel composite evaporators have been widely used for SDIE, but it is still challenging for the hydrogel evaporators to achieve uniform distribution of the light absorbing nanomaterials and at the same time possess satisfactory evaporation rate, durability and environmental applicability. We developed a 3D hydrogel evaporator with an asymmetric structure for high-efficiency SDIE. Natural kapok fibers, an important lignocellulosic plant fiber with a hollow structure, are decorated with MXene nanosheets for construction of one-dimensional photothermal conversion network. The top composite hydrogel serves as the light-absorption layer where MXene-modified kapok fibers are evenly dispersed in PVA hydrogel, while the bottom PVA hydrogel with an oriented structure acts as water delivery path. The evaporator exhibits a high solar evaporation rate and efficiency (2.49 kg·m-2·h-1 and 91.5 %, respectively) under one sun irradiation (1 kW·m-2). Even in a high salinity brine, emulsion and corrosive solutions, the evaporator can work normally with a slightly decreased evaporation rate. The 3D hydrogel evaporator with long-term stability and durability shows promising applications in purification of seawater and different waste water.
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Hidrogéis , Nanoestruturas , Elementos de Transição , Vapor , NitritosRESUMO
Melioration of the through-plane thermal conductivity (TC) of thermal interface materials (TIMs) is a sore need for efficient heat dissipation to handle an overheating concern of high-power-density electronics. Herein, we constructed a snail shell-like thermal conductive framework to facilitate vertical heat conduction in TIMs. With inspiration from spirally growing calcium carbonate platelets of snail shells, a facile double-microrod-assisted curliness method was developed to spirally coil boron nitride nanosheet (BNNS)/aramid nanofiber (ANF) laminates where interconnected BNNSs lie along the horizontal plane. Thus, vertical alignment of BNNSs in the resultant TIM was achieved, exhibiting a through-plane TC enhancement of â¼100% compared to the counterpart with randomly distributed BNNSs at the same BNNS addition (50 wt %). The Foygel's nonlinear model revealed that this unique snail shell-like BNNS framework reduced interfacial thermal resistance by 4 orders of magnitude. Our TIM showed superior interfacial thermal dissipation efficiency, leading to a temperature reduction of 42.6 °C for the LED chip compared to the aforementioned counterpart. Our work paves a valuable way for fabricating high-performance TIMs to ensure reliable operation of electrical devices.
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The advancement of intelligent and biodegradable respiratory protection equipment is pivotal in the realm of human health engineering. Despite significant progress, achieving a balance between efficient filtration and intelligent monitoring remains a great challenge, especially under conditions of high relative humidity (RH) and high airflow rate (AR). Herein, we proposed an interfacial stereocomplexation (ISC) strategy to facilitate intensive interfacial polarization for poly(lactic acid) (PLA) nanofibrous membranes, which were customized for machine learning-assisted respiratory diagnosis. Theoretical principles underlying the facilitated formation of the electroactive phase and aligned PLA chains were quantitatively depicted in the ISC-PLA nanofibers, contributing to the increased dielectric constant and surface potential (as high as 2.2 and 5.1 kV, respectively). Benefiting from the respiration-driven triboelectric mechanisms, the ISC-PLA demonstrated a high PM0.3 filtration efficiency of over 99% with an ultralow pressure drop (75 Pa), even in challenging circumstances (95 ± 5% RH, AR of 85 L/min). Furthermore, we implemented the ISC-PLA with multifunction respiratory monitoring (response time of 0.56 s and recovery time of 0.25 s) and wireless transmission technology, yielding a high recognition rate of 83% for personal breath states. This innovation has practical implications for health management and theoretical advancements in respiratory protection equipment.
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Umidade , Aprendizado de Máquina , Nanofibras , Poliésteres , Poliésteres/química , Nanofibras/química , Humanos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodosRESUMO
Fire-retardant coatings represent a universal cost-effective approach to providing fire protection for various substrates without compromising substrates' bulk properties. However, it has been attractive yet highly challenging to create waterborne polymeric fire-retardant coatings combining high-efficiency, generally strong adhesion, and self-repairability due to a lack of rational design principles. Inspired by mussel's unique adhesive, self-healing, and char-forming mechanisms, herein, a "group synergy" design strategy is proposed to realize the combination of self-healing, strong adhesion, and high efficiency in a fully polymeric fire-retardant coating via multiple synergies between catechol, phosphonic, and hydroxyethyl groups. As-created fire-retardant coating exhibits a rapid room-temperature self-healing ability and strong adhesion to (non)polar substrates due to multiple dynamic non-covalent interactions enabled by these groups. Because these functional groups enable the formation of a robust structurally intact yet slightly expanded char layer upon exposure to flame, a 200 µm-thick such coating can make extremely flammable polystyrene foam very difficult to ignite and self-extinguishing, which far outperforms previous strategies. Moreover, this coating can provide universal exceptional fire protection for a variety of substrates from polymer foams, and timber, to fabric and steel. This work presents a promising material design principle to create next-generation sustainable high-performance fire-retardant coatings for general fire protection.
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Recently, solar-driven interfacial evaporation (SDIE) has been developed quickly for low-cost and sustainable seawater desalination, but addressing the conflict between a high evaporation rate and salt rejection during SDIE is still challenging. Here, a spatial confinement strategy is proposed to prepare the gel composite solar evaporator (SCE) by loading one thin hydrogel layer onto the skeleton of a carbon aerogel. The SCE retains the hierarchically porous structure of carbon aerogels with an optimized water supply induced by dual-driven forces (capillary effects and osmotic pressure) and takes advantage of both aerogels and hydrogels, which can gain energy from air and reduce water enthalpy. The SCE has a high evaporation rate (up to 4.23 kg m-2 h-1 under one sun) and excellent salt rejection performance and can maintain structural integrity after long-term evaporation even at high salinities. The SDIE behavior, including heat distribution, water transport, and salt ion distribution, is investigated by combining theoretical simulations and experimental results. This work provides new inspiration and a theoretical basis for the development of high-performance interfacial evaporators.
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Conductive organohydrogels have gained increasing attention in wearable sensors, flexible batteries, and soft robots due to their exceptional environment adaptability and controllable conductivity. However, it is still difficult for conductive organohydrogels to achieve simultaneous improvement in mechanical and electrical properties. Here, we propose a novel "water vapor assisted aramid nanofiber (ANF) reinforcement" strategy to prepare robust and ionically conductive organohydrogels. Water vapor diffusion can induce the pre-gelation of the polymer solution and ensure the uniform dispersion of ANFs in organohydrogels. ANF reinforced organohydrogels have remarkable mechanical properties with a tensile strength, stretchability and toughness of up to 1.88 ± 0.04 MPa, 633 ± 30%, and 6.75 ± 0.38 MJ m-3, respectively. Furthermore, the organohydrogels exhibit great crack propagation resistance with the fracture energy and fatigue threshold as high as 3793 ± 167 J m-2 and â¼328 J m-2, respectively. As strain sensors, the conductive organohydrogel demonstrates a short response time of 112 ms, a large working strain and superior cycling stability (1200 cycles at 40% strain), enabling effective monitoring of a wide range of complex human motions. This study provides a new yet effective design strategy for high performance and multi-functional nanofiller reinforced organohydrogels.
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Besides their limited preservation capacity and low biosafety, traditional fruit preservation procedures exacerbate "white pollution" because they utilize excessive plastic. Herein, an environmentally friendly one-pot method was developed to obtain degradable polyvinyl alcohol (PVA), where the hydroxyl radicals generated through the reaction between hydrogen peroxide (H2O2) and iron ions functioned to oxidize PVA. The oxidized PVA (OPVA-1.0) with abundant ketone groups, reduced crystallinity, and short molecular chains was completely degraded into H2O and CO2 after being buried in the soil for â¼60 days. An improvement in its degradation rate did not weaken the mechanical properties of OPVA-1.0 compared to other modified PVA films because the adverse effect of decreased crystallinity on its mechanical performance was offset by its ion coordination. Alternatively, the tensile strength or toughness of OPVA-1.0 was enhanced due to its internal multi-level interactions including molecular chain entanglement, hydrogen bonding, and metal coordination bonds. More interestingly, OPVA-1.0 was water-welded into various products in a recyclable way owing to its reversible physical bonds, where it was sprayed, dipped, or brushed conformally onto different perishable fruits to delay their ripening by 5-14 days. Based on the cellular biocompatibility and biosafety evaluations in mice, OPVA-1.0 obtained by the facile oxidation strategy was demonstrated to alleviate "white pollution" and delay the ripening of fruits effectively.
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The concept of bio-inspired gradient hierarchies, in which the well-defined MOF nanocrystals serve as active nanodielectrics to create electroactive shell at poly(lactic acid) (PLA) nanofibers, is introduced to promote the surface activity and electroactivity of PLA nanofibrous membranes (NFMs). The strategy enabled significant refinement of PLA nanofibers during coaxial electrospinning (â¼40 % decline of fiber diameter), accompanied by remarkable increase of specific surface area (nearly 1.5 m2/g), porosity (approximately 85 %) and dielectric constants for the bio-inspired gradient PLA (BG-PLA) NFMs. It largely boosted initial electret properties and electrostatic adsorption capability of BG-PLA NFMs, as well as charge regeneration by TENG mechanisms even under high-humidity environment. The BG-PLA NFMs thus featured exceptionally high PM0.3 filtration efficiencies with well-controlled air resistance (94.3 %, 163.4 Pa, 85 L/min), in contrast to the relatively low efficiency of only 80.0 % for normal PLA. During the application evaluation of outdoor air purification, excellent long-term filtering performance was demonstrated for the BG-PLA for up to 4 h (nearly 98.0 %, 53 Pa), whereas normal PLA exhibited a gradually declined filtration efficiency and an increased pressure drop. Moreover, the BG-PLA NFMs of increased electroactivity were ready to generate tribo-output currents as driven by respiratory vibrations, which enabled real-time monitoring of electrophysiological signals. This bio-inspired gradient strategy opens up promising pathways to engender biodegradable nanofibers of high surface activity and electroactivity, which has significant implications for intelligent protective membranes.
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Nanofibras , Poliésteres , Nanofibras/química , Poliésteres/química , Material Particulado/química , Humanos , Poluentes Atmosféricos/química , Filtração , Monitoramento Ambiental/métodosRESUMO
Recent years have witnessed the explosive development of highly sensitive smart sensors based on conductive polymer foam materials. However, the design and development of multifunctional polymeric foam composites as smart sensors applied in complex solvent and oil environments remain a critical challenge. Herein, we design and synthesize vinyl-terminated polytrifluoropropylmethylsiloxane through anionic ring-opening polymerization to fabricate fluorosilicone rubber foam (FSiRF) materials with nanoscale wrinkled surfaces and reactive Si-H groups via a green and rapid chemical foaming strategy. Based on the strong adhesion between FSiRF materials and consecutive oxidized ketjen black (OKB) nano-network, multifunctional FSiRF nanocomposites were prepared by a dip-coating strategy followed by fluoroalkylsilane modification. The optimized F-OKB@FSiRF nanocomposites exhibit outstanding mechanical flexibility in wide-temperature range (100 cycle compressions from -20 to 200 °C), structure stability (no detached particles after being immersed into various aqueous solutions for up to 15 days), surface superhydrophobicity (water contact angle of 154° and sliding angle of â¼7°), and tunable electrical conductivity (from 10-5 to 10-2 S m-1). Additionally, benefiting from the combined actions of multiple lines of defense (low surface energy groups, physical barriers, and "shielding effect"), the F-OKB@FSiRF sensor presents excellent anti-swelling property and high sensitivity in monitoring both large-deformation and tiny vibrations generated by knocking the beaker, ultrasonic action, agitating, and sinking objects in weak-polar or nonpolar solvents. This work conceivably provides a chemical strategy for the fabrication of multifunctional polymeric foam nanocomposite materials as smart sensors for broad applications.
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Conductive organohydrogels are promising for strain sensing, while their weak mechanical properties, poor crack propagation resistance and unstable sensing signals during long-term use have seriously limited their applications as high-performance strain sensors. Here, we propose a facile method, i.e., solvent exchange assisted hot-pressing, to prepare strong yet tough, transparent and anti-fatigue ionically conductive organohydrogels (ICOHs). The densified polymeric network and improved crystallinity endow ICOHs with excellent mechanical properties. The tensile strength, toughness, fracture energy and fatigue threshold of ICOHs can reach 36.12 ± 4.15 MPa, 54.57 ± 2.89 MJ m-3, 43.44 ± 8.54 kJ m-2 and 1212.86 ± 57.20 J m-2, respectively, with a satisfactory fracture strain of 266 ± 33%. In addition, ICOH strain sensors with freezing and drying resistance exhibit excellent cycling stability (10 000 cycles). More importantly, the fatigue resistance allows the notched strain sensor to work normally with no crack propagation and output stable and reliable sensing signals. Overall, the unique flaw-insensitive strain sensing makes ICOHs promising in the field of wearable and durable electronics.
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MXene-based thermal camouflage materials have gained increasing attention due to their low emissivity, however, the poor anti-oxidation restricts their potential applications under complex environments. Various modification methods and strategies, e.g., the addition of antioxidant molecules and fillers have been developed to overcome this, but the realization of long-term, reliable thermal camouflage using MXene network (coating) with excellent comprehensive performance remains a great challenge. Here, a MXene-based hybrid network comodified with hyaluronic acid (HA) and hyperbranched polysiloxane (HSi) molecules is designed and fabricated. Notably, the presence of appreciated HA molecules restricts the oxidation of MXene sheets without altering infrared stealth performance, superior to other water-soluble polymers; while the HSi molecules can act as efficient cross-linking agents to generate strong interactions between MXene sheets and HA molecules. The optimized MXene/HA/HSi composites exhibit excellent mechanical flexibility (folded into crane structure), good water/solvent resistance, and long-term stable thermal camouflage capability (with low infrared emissivity of ≈0.29). The long-term thermal camouflage reliability (≈8 months) under various outdoor weathers and the scalable coating capability of the MXene-coated textile enable them to disguise the IR signal of various targets in complex environments, indicating the great promise of achieved material for thermal camouflage, IR stealth, and counter surveillance.