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• It is a timely and comprehensive review on the quick progress of Zn anode interface. • A detailed analysis of the challenges hindering stable zinc anode interface are introduced. • Strategies to tailor Zn metal anode interface are presented. • Highly stable Zn anode interface is promising for commercial applications. In recent years, zinc metal batteries (ZMBs) have become an important alternative to lithium-ion batteries due to their high energy density, high safety, and low cost. However, the development of ZMBs still encounters several challenges such as dendrite growth, hydrogen evolution, corrosion, and passivation. These issues likely contribute to the instability of the zinc anode/electrolyte interface, hindering practical applications of zinc batteries. Recently, extensive research on the zinc anode/electrolyte interface has been conducted globally; therefore, a comprehensive review is warranted. Initially, this paper discusses the fundamentals of the zinc anode interface and the related issues arising from its intrinsic instability. Subsequently, it systematically summarizes various effective strategies for regulating the interface including zinc anode surface modification, electrolyte regulation, zinc anode structure design, and separator optimization. Finally, it concludes with a prospect on addressing challenges and providing perspectives for optimizing the zinc anode interface in order to achieve high-performance ZMBs. [ABSTRACT FROM AUTHOR]

• A conductive fiber with synergistic conductive network is prepared for strain sensor. • The synergistic effect is beneficial for tunable and balanced sensing performances. • The sensor shows great potential for human motion monitoring and tactile sensing. • The fiber displays good photothermal performances even under 150% strain. With the rapid development of portable electronic products, smart wearable devices show great application potential in personalized motion monitoring, health monitoring and even in human-machine interaction. In particular, high-performance flexible fiber-shaped strain sensors are receiving more and more attention because they can be well integrated with clothes or human skin for real-time human activities monitoring. However, achieving improved sensitivity, wide detection range, diverse applications and easy operation of them remains a challenge. Here, we adopt a simple wet-spinning technique to prepare a porous fiber-shaped carbon nanotubes (CNTs)/silver nanoparticles (AgNPs)/thermoplastic polyurethane (TPU) fiber (CATF) for high-performance strain sensor, of which the synergistic conductive network of CNTs and AgNPs enables a wide detection range (∼248 %), high sensitivity (GF > 4295), fast response/recovery time (120 ms/140 ms) and excellent stability. Interestingly, strain sensing range and sensitivity of the sensor can be tuned by changing the AgNPs loading to make it suitable for different application scenarios. All the merits of the sensor make it capable for diverse human movements monitoring, pronunciation recognition, and gesture recognition. More importantly, our prepared CATF strain sensor can be easily weaved into wearable smart textiles, showing great potential for tactile sensing to realize multi-touch and pressure tracking. Finally, the CATF also displays efficient photothermal conversion capability even under different tensile strains up to 150 %, showing great potential in human body thermal management to improve the wearing comfort of wearable electronic fabric. [ABSTRACT FROM AUTHOR]

[Display omitted] • An aligned TPU electrospun mat with wave-like structure is selected as the substrate. • The microcrack structure is constructed by pre-stretching technology. • The strain sensor can achieve sign language interpretation and multi-angle recognition. • The visual sensing function expands the application area of the CNTs/AgNWs/TPU sensor. Recently, flexible strain sensors have attracted great attention on account of the application potential in medical treatment, flexible prosthetics and human–machine interaction. Nevertheless, traditional uniaxial strain sensors cannot detect movement in different directions, limiting the applications in sensing technologies. In addition, it is still a significant challenge to simultaneously acquire visualized and high-performance strain sensors. Here, a highly flexible sensor with visual sensing function was fabricated by spraying silver nanowires (AgNWs)/carbon nanotubes (CNTs) ink on the aligned thermoplastic polyurethane (TPU) electrospun mat. The sensing performances of AgNWs/CNTs aligned TPU fluorescent mats (ACUM-F) are individually explored in vertical and parallel directions. Herein, the ACUM-F in vertical can exhibit high sensitivity (gauge factor (GF) up to 244.3), wide working range (0.1 ∼ 380 % strain), fast response/recovery time (80 ms/80 ms), good sensing durability and reproducibility (1000 stretching/releasing test cycles). Furthermore, ACUM-F is assembled as strain sensors to monitor various human body movements, which can achieve sign language interpretation through finger gesture monitoring, demonstrating its great potential in human–machine interaction. The direction-aware application of novel multidirectional sensors with visual sensing functions may bring inspiration for a new era of flexible electronics development. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-adhesive, self-healing and multimodal sensing organohydrogel was prepared. • Environmental stability of organohydrogel is enhanced by glycerol and PA. • The organohydrogel shows wide humidity response and temperature detection range. • The organohydrogel displays reliable strain sensing ability in a wide strain range. Conductive hydrogel (CH) has drawn widespread interest in flexible electronics, human–computer interaction, and electronic skins (e-skins). However, it is challenging to integrate satisfactory self-adhesion, self-healing, environmental stability, and multi-stimulus response into a single CH system. Herein, a conductive nanocomposite organohydrogel with the above characteristics is well-designed and developed via incorporating carboxylic cellulose nanofibers-carrying carboxylic carbon nanotubes (C-CNTs) and phytic acid (PA) into polyacrylamide network through free-radical polymerization plus glycerol solvent displacement strategy, aiming for a high-performance multimodal sensing platform. Here, the coupling of C-CNTs and ionization of PA contributes a favorable conductivity, and the coexistence of glycerol and PA is beneficial for the formation of amounts of hydrogen bonds that endow the organohydrogel with outstanding stretchability, self-healing, and favorable adhesion in a wide temperature range of −30 to 60 °C. Besides, the resultant organohydrogel can effectively detect multiple external stimuli, manifesting high strain sensitivity over a broad strain range (0–1566 %), good humidity detectability at 0–85 % RH, and reliable thermosensation capability over a wide temperature window (−30 to 60 °C). Significantly, the application of the organohydrogel as e-skins are conducted to detect full-range human activity movements even in the extreme environments, identify hand gestures, and recognize the spatial distribution of humidity in noncontact sensing. All these indicate the preponderance of our organohydrogel in the fields of flexible smart electronics. [ABSTRACT FROM AUTHOR]

• Layer-by-layer scraping can produce a powerful shearing effect for UHPE/GNPs gel. • Strong shearing induced dense stacking and ordered alignment of GNPs and PE chains. • The dense and ordered structure drastically enhanced in-plane TC up to 28.88 W/mK. • The solar-thermal conversion ability was also improved by the ordered structure. The simultaneous achievement of ordered alignment for fillers and polymer matrix is highly desired in polymer-based thermally conductive composites, but it is still extremely challenging. Herein, we put forward a layer-by-layer scraping (LbLS) method to simultaneously arrange ultra-high molecular weight polyethylene (UHPE) chains and graphene nanoplates (GNP) into a highly oriented structure. When UHPE/GNP gel suffering the strong shearing effect during LbLS process, the inner UHPE chains and GNP were dragged and orderly arranged along shearing direction, and these oriented structures were retained after rapidly drying by distillation. After layer-by-layer stacking, nacre-like UHPE/GNP films with tightly layered structure were obtained. By adjusting the scraping gap from 200 to 50 μm, the oriented structure can be effectively reinforced with the Herman orientation factors f increasing from 0.83 to 0.88 for GNP and 0.75 to 0.82 for UHPE chains. The highly ordered structure can form a tight and oriented thermal conduction network with low interfacial thermal resistance in plane. The LbLS composite film thus significantly enhanced the in-plane thermal conductivity up to 28.88 W/mK, compared with traditional solution casting film (9.63 W/mK). Moreover, the highly oriented structure can significantly increase the solar-thermal conversion performance (58.1 °C@100 mW/cm2) by improving its light absorption ability comparing to that of solution casting film. Besides, the mechanical strength and toughness that depend on the filler and chain alignment were effectively increased by the oriented structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Breathable electronic skin with 3D skeleton and microcrack structures is designed. • High sensitivity and wide working range are realized for the strain sensor. • The strain sensor can accurately distinguish various human movements. • The device has photo-thermo-electric and self-powered sensing applications. With the rapid development of wearable electronic, electronic skin with excellent performance for human motion detection have been widely investigated recently. In this work, a multifunctional electronic skin with three-dimensional conductive network skeleton was prepared based on synergistic conductive filler (carboxylated multi-walled carbon nanotubes (C-MWCNT) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS)) decorated breathable thermoplastic polyurethane (TPU) electrospinning fibrous membrane. Then, microcrack structure was constructed via pre-stretching and the strain sensitivity of the resultant C-MWCNT/PEDOT:PSS/TPU (CPT) conductive fibrous membrane could be effectively adjusted by changing the microcrack density. Due to the three-dimensional conductive network skeleton, microcrack structure and the bridging effect of C-MWCNT between the adjacent crack fragments, ethylene glycol treated CPT (mass ratio of C-MWCNT and PEDOT:PSS is 9/1) (e-CPT 9/1) strain sensor exhibited high sensitivity (6008.3), wide response range (680 %), fast response/recovery time (200 ms/200 ms), low detection limit (0.5 %), excellent durability and repeatability (6000 cycles). The excellent strain sensing performances enables it to accurately monitor motion activities and physiological signals, and can also be used as a smart sensing glove to identify different letters gesture and numeric gestures. Furthermore, owing to the photothermal conversion ability and thermoelectric effect of C-MWCNT and PEDOT:PSS, the obtained e-CPT 9/1 device also displayed efficient "light-thermal-electric" conversion ability and showed the great potential as self-powered strain sensor. [ABSTRACT FROM AUTHOR]

[Display omitted] • Degradable interfacial solar vapor generator (DISVG) was successfully fabricated. • Effective thermal localization is achieved on the DISVG by a double-layer design. • The DISVG shows an outstanding evaporation rate of 3.88 kg m-2 h−1 under 1 sun. • The DISVG shows excellent salt resistance and dye removal capacity. The interfacial solar vapor generator (ISVG) has emerged as a promising solution to address freshwater scarcity. The enhancement of thermal localization and suppression of salt crystallization are recognized as the design key factors for ISVG. In this study, we successfully fabricated a novel double-layer structure degradable interfacial solar vapor generator (DISVG) utilizing chitosan monolith (CM) with honeycomb porous morphology as carrier material, while employing MXene nano-sheets as solar absorber. The fabrication process involved facile chemical crosslinking and dip-coating methods. The incorporation of the double-layer structure in the DISVG plays a significant role in achieving effective thermal localization, thereby minimizing heat transfer to bulk water. Consequently, this feature results in a remarkable improvement in evaporation rate while simultaneously enhancing salt resistance. The DISVG demonstrated an outstanding evaporation rate of 3.88 kg m-2 h-1 under 1 sun (1 kW m-2) irradiation and effectively removed more than 99% of salt and dyes in water. Interestingly, even without the presence of MXene, the DISVG still achieved efficient evaporation at a rate of 2.63 kg m-2 h-1 under 1 sun irradiation. Moreover, both DISVGs exhibited stability over extended period of operation without any rate decay. This study not only presents a novel approach for the progress of environmentally friendly and cost-efficient ISVG but also offers valuable insights into overcoming the trade-off between thermal localization and salt resistance in such systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • ANF-carbonized welding is used to reduce the ITR of 3D graphene architecture. • PCM containing graphene architecture shows a TC of 4.85 W/mK at 4.26 vol% content. • Thermal conductive architecture achieves the rapid heat transfer/storage in PCM. • Graphene architecture enables PCM solar/electric-to-thermal conversion capacity. Graphene-based porous architectures are promising in addressing the poor thermal conductivity, leakage, shape stability problems of organic phase change materials (PCMs), meanwhile endowing them with excellent solar/electric-to-heat conversion ability, but they are still limited by the high interfacial thermal/electrical resistance in architectures caused by organic "binders". In this work, in view of the excellent gel ability of aramid nanofibers (ANF) and its highly ordered conjugate molecular structure, a promising graphene porous architecture assisted by ANF was constructed by unidirectional freeze casting coupled with carbonization welding technique. Due to the similar graphite lattice structure of ANF-derived carbonization and graphene, the interfacial thermal/electrical resistance in highly vertically oriented graphene architecture was greatly reduced. As a result, the PCMs composite encapsulated by the graphene architecture carbonizing at 1500 °C exhibited an outstanding thermal conductivity of as high as 4.85 W/mK at only 4.26 vol%, which enables a rapid heat transfer and storage in PCM composite. The honeycomb porous graphene architecture with high porosity can accommodate sufficient PCMs for energy storage, showing a high latent heat enthalpy of 149.7 J/g with excellent shape stability during phase change process. More importantly, the graphene architecture endows PCM composites with excellent solar/electric-to-thermal conversion capacities, which not only expands the types of energy stored by PCMs, but is also promising in the thermal management application requiring a continuous and stable temperature environment. [ABSTRACT FROM AUTHOR]

• CB particles were decorated on PDMS foam to fabricate a flexible porous piezoresistive sensor. • The sensor possesses a very high linear working range (up to 91%). • A fast response time (45 ms) and superior durability (>15000 cycles) have both been achieved. • The sensor possess an excellent hydrophobic property (water contact angle up to 149°). • The CB/PDMS foam can also be used for oil/water separation. The achievement of favorable pressure sensor integrated with large linear working range, high sensitivity and excellent response durability is still a great challenge for flexible and wearable piezoresistive materials. In this paper, a facile and scalable strategy is proposed to fabricate a porous foam sensor based on carbon black/polydimethylsiloxane (CB/PDMS). CB particles were decorated onto the surface of the cell walls and some particles were embedded into PDMS matrix after the ultrasonication treatment. The density and porosity of the foam are 0.13 g/cm3 and 76.1%, respectively. A very high linear working range (up to 91%), an excellent response stability, a fast response time (45 ms), and a superior durability (>15000 cycles) are achieved synchronously. Here, the large linear sensing range is mainly related to the nice CB conductive network on the cross-linked PDMS foam and the high modulus and elasticity of the composite material, which ensure the homogeneous deformation of the foam under compression. It is worth noting that the response behavior of CB/PDMS foam is maintained well even in water owing to its excellent hydrophobic property (water contact angle up to 149°), indicating that this material can be used as a waterproof piezoresistive sensor. Our CB/PDMS foam is then assembled as a wearable sensor, and it exhibits nice capability of monitoring human body motions, such as the bending of fingers and elbow, walking, jumping and squatting, etc. The porous foam sensor also has a good oil/water separation ability, showing a multifunctional characteristic. [ABSTRACT FROM AUTHOR]

• A comprehensive review of the recent progress with cobalt-based electrodes for sodium-ion batteries is presented. • The electrochemical mechanisms are pointed out. • The relationship between crystalline structure and electrochemical performance are discussed. • The strategies to enhance the overall electrochemical performance of cobalt-based cathode and anode materials are discussed. The demand for grid-scale energy storage systems has rapidly grown over recent years, to meet the requirements of structural innovation within the energy industry. Due to their inexpensive manufacturing and operating costs, and the similar electrochemical mechanism with the well-established lithium-ion batteries (LIBs), sodium ion batteries (SIBs) have been considered as an attractive candidate for grid-scale energy storage systems. A variety of cobalt-based cathode and anode materials, including cobalt oxides, cobalt chalcogenides and layered sodium cobaltates, have been synthesized and evaluated for sodium storage within the academic literature. In this article, we present a comprehensive review of the recent progress with cobalt-based electrodes (both as an anode and cathode material) used in SIBs. In detail, the electrochemical mechanisms, advantages and disadvantages, the relationship between crystalline structure and electrochemical performance and strategies to enhance the overall electrochemical performance of cobalt-based cathode and anode materials are discussed. Up to now, some cathode materials have already reached a high energy density, which is comparable to commercial LIBs. Furthermore, some cobalt-based materials can maintain a high Coulombic efficiency of over 99% with high reversible capacity during long cycling life. These encouraging results, allow such cobalt-based electrode materials to be a potential solution for grid-scale SIB systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • PDA and PPy nanofibers coated foam with narrow orifice structure was developed. • The multi-scale closure mechanism contributed to an ultra-high sensitivity. • The sensor exhibits fast response time, high linearity and excellent stability. • The foam sensor can detect walking, running, yoga postures and sleeping positions. Commercial foam based piezoresistive sensors are promising flexible sensing units for wearable devices, while they suffer from relative low sensitivity, especially in low pressure range. Herein, inspired by scorpion slit organs, multi-scale closure piezoresistive sensors are developed by self-polymerization of a polydopamine (PDA) layer and a polypyrrole nanofibers (PPy NFs) layer on polyurethane (PU) foam, and constructing a macroscopic narrow orifice configuration (NOC), which allows the generation of a great mount of conductive paths at low pressure. The synergetic effects of inner space closure, pore collapse, and PPy NFs contact contributed to an ultra-high sensitivity of 0.8251 kPa−1, which surpasses reported foam-based sensors. The developed NOC foam possesses fast response time and recovery time (120 ms and 100 ms), high linearity, and excellent stability. Moreover, the sensor can be used to precisely detect the human walking, running, and jumping behaviors, and the grabbing force. When integrated into a sensing array, the NOC PPP foams demonstrated excellent potential to be used in human activity monitoring such as yoga postures and sleeping positions. This work provides new thoughts for designing biomimetic highly sensitive piezoresistive sensors and enhancing the foam stability using PPy NFs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ammonium polyphosphate functionalized BNNS (BNNS@APP) was prepared by one-step wet ball milling method. • The macromolecular APP play the role of organic "binders" to construct 3D BNNS skeleton. • The 3D BNNS@APP skeleton with a highly oriented structure was obtained by unidirectional freezing. • The EP/BNNS@APP composite presented excellent thermal conductivity and flame retardancy. Three-dimensional (3D) boron nitride skeleton has a promising prospect in improving the thermal conductivity and flame retardancy of polymer composites, yet the problems of interface thermal resistance and combustion collapse in the skeleton caused by organic adhesives still need to be solved. In this work, macromolecular flame retardancy, ammonium polyphosphate (APP) with high polymerization degree, was firstly used to modify and assemble boron nitride nanosheets (BNNS) into 3D thermally conductive skeleton, in which APP with rich amino groups can result in the strong grafting modification to reduce the interfacial thermal resistance in BNNS skeleton, meanwhile, the catalytic carbonization of APP can reinforce the 3D skeleton barrier without collapse during combustion. Typically, one-step wet ball-milling with assisted APP was used to exfoliate and modify BNNS, followed by unidirectional freezing to achieve 3D BNNS@APP skeleton with highly oriented structure. As expected, the constructing 3D skeleton with low interfacial thermal resistance can effectively form a heat transfer path in polymer matrix. The obtained epoxy-based composite showed a high thermal conductivity of 3.28 W/mK at 9.28 vol% BNNS@APP. Meanwhile, the producing 3D skeleton barrier during combustion induced the significant improvement in flame retardancy, with heat release rate (HRR) and total heat release (THR) decreasing by 68.3% and 52.7%, respectively. This work provides a new adhesive choice in constructing 3D thermal conductive and flame retardant skeleton, which exhibits high potential in thermal management application. [ABSTRACT FROM AUTHOR]

Graphical abstract This study reports an aligned wave-like carbon nanotubes (CNTs)/thermoplastic polyurethane (TPU) fibrous network based strain sensor with ultra-wide sensing range, low detection limit, fast response rate and excellent stability, which provides a good candidate for wearable devices and artificial intelligence (AI). Highlights • An aligned conductive fibrous mat based strain sensor with wave-like structure was fabricated. • The sensor possesses an ultrahigh stretchability of 900%, combining with an excellent stability. • An ultralow detection limit (0.5%) and a fast response time of 70 ms have both been achieved. • The sensing behaviors of the CNTs/TPU fibrous sensor agree well with the tunneling theory. • The designed wave-like structure and the joints structure caused the fine sensing performances. Abstract Recently, flexible strain sensors with large stretchability, high sensitivity and excellent stability have been widely concerned owing to their potential applications in wearable electronic devices. However, the challenge of narrow sensing range still remains for strain sensors with high performance. In this paper, we proposed a facile, cost-effective and scalable technology to manufacture the carbon nanotubes (CNTs)/thermoplastic polyurethane (TPU) fibrous strain sensor with aligned wave-like structure. Through electrospinning technique, we prepared an aligned TPU fibrous mat, then used a simple and effective assembly approach to induce CNTs to wrap TPU fibrous mat through ultrasonication. The sensing properties of CNTs/TPU mats in vertical and parallel directions were investigated, respectively. The sensing behaviors of the two sensors both agreed well with the tunneling theory. Compared with the random CNTs/TPU mats and parallel direction sample, the aligned CNTs/TPU fibrous mats in vertical direction possessed an ultra-high stretchability (900%) and excellent durability (10,000 cycles at the strain of 200%). An ultra-low detection limit (0.5%) and fast response time of 70 ms were also achieved, exhibiting a favorable sensitivity. The generation of the wave-like structure and the joints structure in the designed conductive network, which could affect the evolution of the conductive paths subsequently, led to these excellent sensing performances. The CNTs/TPU mats strain sensor was then assembled to monitor both subtle human motions, like cheek bulging and phonation; and vigorous human motions, like leg squatting and elbow bending, both showing excellent sensing performances. The present paper provides a good candidate for potential applications as artificial skins, human-activity monitoring and personal healthcare. [ABSTRACT FROM AUTHOR]

Graphical abstract The multilayered ACPCs based on PP/MWCNTs composites were prepared with outstanding conductive anisotropy, excellent current-carrying capability and directional heat dissipation, demonstrating the applications for electrical and thermal management. Highlights • Multilayered composites were fabricated via a facile but environmental friendly way. • Such composites show remarkable anisotropic electrical and thermal conductivity. • Such composites exhibit strong interfacial strength and enhanced thermal stability. • Such composites can be easily processed into desired macroscopic shapes. • This approach can be easily scaled up for industrial production. Abstract Multilayered objects are some of the most common composites in nature with outstanding performance that cannot be achieved by a single component. To expand the application of multilayered composites with excellent anisotropic properties, facile and environmental friendly fabrication methods and low-cost raw materials are unambiguously required. The Chinese traditional food called "thousand-layer pie" is an example of such composites with multilayered structure, showing visual attractiveness and having delicious taste. Borrowing the idea from the method of preparing this food, anisotropic conductive polymer composites (ACPCs) with alternating microlayers of pure polypropylene (PP) and PP filled multi-walled carbon nanotubes (PPCNTs) were prepared by a combined polymer melt processing technique. The multilayered structure endowed the ACPCs with inner layer conduction but interlayer insulation. The electrical conductivity in X direction reached up to 1 S/m and exhibited a value almost 16 orders of magnitude higher than the value in Z direction, which was by far the most remarkable conductive anisotropy compared with the reported counterparts. The anisotropic functionality of the ACPCs enabled them to be used in electrical and thermal management applications, such as subminiature integrated circuits, highly reliable electrical interconnects and anisotropic thermal conduction. Considering the low-cost raw materials used and the facile preparation process, this approach can be scaled up for industrial production, promoting such ACPCs with high performance and functionality to be implemented in a variety of applications. [ABSTRACT FROM AUTHOR]

• Synthesized supramolecular elastomer contains disulfide bonds and quadruple H-bonds. • The elastomer has strain-hardening, self-standing, and self-healing properties. • Silica nanoparticles further enhanced energy absorption and hindered relaxation. • Sacrificial bonds and nanoparticles contributed to the high energy absorption. Developing protective materials with intelligent and stimuli-responsive properties is indispensable for safety protection. However, combining contradictory characteristics into a single polymer is challenging, such as high mechanical strength, impact protection, and self-healing properties. Herein, a strain-hardening supramolecular polyurethane nanocomposite (SPN) with high mechanical strength and unique impact protection characteristics is synthesized by incorporating quadruple hydrogen bonds (H-bonds), disulfide bonds, and modified silica nanoparticles into polyurethane elastomer. Benefiting from the dynamic break and re-form characteristic of quadruple H-bonds and the stress dissipation behavior of nanoparticles, SPN exhibits high energy absorption efficiency and impact protection properties. During the drop ball striking test, the impact energy absorption efficiencies reached 90%, and the buffer time of impact was significantly longer than common buffering materials. The SPN exhibited excellent stretchability and self-healing ability, ascribing to disulfide metathesis and H-bonds association. Moreover, the prepared SPN could be easily processed through a hot press and showed negligible creeping. The developed SPN could serve as a novel self-standing impact protective material that offers promising prospects in sports, transportation, and aerospace fields. [ABSTRACT FROM AUTHOR]

• Waterproof conductive fiber with microcracked synergistic conductive layer was designed. • High sensitivity and wide working range were achieved for the conductive fiber strain sensor. • Tunable sensing performance was achieved for the conductive fiber strain sensor. • The sensor can precisely distinguish various human movements and physiological signals. With the rapid development of wearable smart electronic devices, flexible strain sensors with high sensitivity in a wide working range are urgently demanded. Meanwhile, good self-cleaning and anti-corrosion properties are also essential for daily use. Herein, a waterproof conductive spandex fiber strain sensor with microcracked synergistic Ag nanoparticles (AgNPs)-carbon nanotubes CNTs conductive layer was designed and fabricated via the solvent swelling, non-solvent-induced phase separation (NIPS), and low surface energy treatment process. Benefiting from the stable synergistic conductive network and the ultrasensitive microcrack structure, the sensor exhibits excellent overall strain sensing performances, including high sensitivity (gauge factor is 48,310 within 335–400% strain), wide working range (0–400%), ultralow detection limit (0.1%), fast response/recovery time (80 ms/100 ms), and long-term fatigue resistance over 10,000 cycles, making it reliably and precisely distinguish both violent human movements and subtle physiological signals. More importantly, strain sensing range and sensitivity of the sensor can also be effectively tunned through changing the AgNPs loading in the synergistic conductive network, enabling it to be applicable for different application scenarios. What's more, the waterproof surface with good self-cleaning and anti-corrosion properties also endows the sensor with great potential for real-time body motion monitoring under humid and underwater environments without being interfered. This study provides a facile one-step method for the fabrication high-performance flexible strain sensor. [ABSTRACT FROM AUTHOR]

Via coextrusion blow film molding, sandwiched functional polymer films (SFPFs) were massively fabricated, whose skin and core layer are respectively low density polyethylene (LDPE) and polyethylene oxide (PEO) phase. Moreover, such SFPFs show rapidly and reversibly switchable transparency during cyclic melting-crystallization process, which can be used for thermo-photo door in photocatalytic reaction system and serve as smart windows achieving programmable luminance and privacy of room by wireless remote control. [Display omitted] • The commercial but low-cost thermoplastics elaborately serve as skin and core layer. • SFPFs were easily fabricated by a cost-efficient and environmentally friendly method. • SPFFs show reversibly and rapidly switchable transparency on cyclic heating cooling. • SPFFs are successfully used for thermo-photo door and serve as smart windows. Polymer functional films (PFFs) with switchable transparency have drawn increasing interests recently for their promising applications. Unfortunately, it still remains a challenge to fabricate large-area temperature-driven PFFs by a facile, continuous and environmentally friendly method. Herein, via coextrusion blow film molding, sandwiched polymer functional films (SPFFs) were massively fabricated, whose skin and core layer are respectively low density polyethylene (LDPE) and polyethylene oxide (PEO) phase. Moreover, such SPFFs show wide range of reversibly switchable transparency and rapid response to varied temperatures during cyclic melting-crystallization process. In view of this, the as-prepared SPFFs can be used for thermo-photo door in photocatalytic reaction system and serve as smart windows. This work proposes a facile, cost-efficient and environmentally-friendly method for developing low-cost, durable and large-area SPFFs, and first builds the relationship between crystallization performance and functional application in industrial product, providing a new pathway to build the functional architecture based on the concept of polymer "structuring" processing. [ABSTRACT FROM AUTHOR]

• Synergistic MXene/CNTs based multifunctional TPU fabric (MCT-fabric) was prepared. • The MCT-fabric strain sensor shows both high sensitivity and broad sensing range. • The MCT-fabric shows superior EMI shielding effectiveness. • The MCT-fabric shows high efficient and long-term stable Joule heating capability. High-performance electronic textile with outstanding strain sensing, electromagnetic interference (EMI) shielding, and Joule heating performances are highly desirable for modern integrated smart wearable electronic devices. Herein, multifunctional electronic textile based on hybrid Ti 3 C 2 T x MXene and carbon nanotubes (CNTs) conductive nanomaterials coated thermoplastic polyurethane (TPU) non-woven fabric (MCT-fabric) is fabricated via a facile dip-coating approach. Based on the synergistic MXene/CNTs conductive coating and pre-stretching induced ultrasensitive microcrack structure, tunable conductive MCT-fabric strain sensor with high sensitivity (GF is as high as 9022), wide sensing range (∼210 %), rapid response/recovery time (140/160 ms), excellent long-term stability and reliability (∼1000 cycles) is successfully constructed. Besides, benefiting from the perfect synergistic conductive network and porous fibrous network structure, the MCT-fabric displays superior EMI shielding effectiveness (∼43 dB for the MCT-fabric with a thickness of 600 μm) and excellent thermal management performance including high Joule heating temperature at relatively low applied voltages, rapid Joule heating response, sufficient heating stability and reliability. This work indicates that the high-performance multifunctional electronic textile has attractive potential for strain sensing, EMI shielding and thermal management applications in artificial intelligence and emerging wearable electronics. [ABSTRACT FROM AUTHOR]

Due to the multiple electronic transmission channels established at the interface between NiMo cores and C 3 N 5 shells, the obtained NiMo@C 3 N 5 hybrids exhibit stable and efficient HER performance in seawater, which is superior to that of commercial Pt/C. [Display omitted] • Multiple electronic transmission channels were established between NiMo and C 3 N 5. • Induced electron redistribution effect optimized the HER reaction pathway. • The NiMo@C 3 N 5 catalyst shows excellent HER performance and stability in seawater. Designing highly efficient and stable electrocatalysts for hydrogen evolution reaction (HER), particularly in seawater, still remains a challenging task. Herein, the unique heterostructures composed of 1D NiMo cores and 2D C 3 N 5 shells (NiMo@C 3 N 5) are rationally designed and demonstrated as the robust HER catalysts in both alkaline electrolytes and natural seawater, where the carbon-based shell can effectively protect the catalyst core from seawater poisoning. Based on the experimental investigation and density functional theory calculation, multiple electronic transmission channels were found to establish at the interface between NiMo cores and C 3 N 5 shells, thus providing efficiently optimized HER pathways to achieve minimized overpotential with a reduced energy barrier of the rate-determining step. More importantly, the NiMo@C 3 N 5 hybrids exhibit stable HER performance with a high Faradaic efficiency of 94.8% in seawater, which is superior to that of commercial Pt/C. All these results can evidently highlight a feasible strategy to develop high-performance HER electrocatalysts via interface engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ionic liquid functionalized BNNS (BNNS@IL) was performed by one-step ball milling. • High-orientation layered EP/BNNS@IL film was fabricated via CLbL blade-casting. • Well-dispersed BNNS@IL is highly stacked in EP matrix along the in-plane direction. • The film showed excellent anisotropic thermal conductivity and flame retardancy. Increasing power density and excess heat production in integrated electronic devices create the strong demand for polymeric thermal management materials with excellent thermal stability, flame retardancy and thermal conductivity. To this end, high-performance ionic liquid-wrapped boron nitride nanosheets (BNNS@IL) were firstly simultaneously exfoliated and flame-retardant functionalized via one-step ball milling process based on the strong mechanochemical action. Epoxy (EP)-based layered films with highly in-plane oriented BNNS@IL were then fabricated by a novel, effective and solvent-free cyclic layer-by-layer (CLbL) blade-casting method. Arising from the highly flat oriented structure and rich flame-retardant functional groups of BNNS@IL, as well as the high compatibility between filler and matrix, the as-fabricated EP/BNNS@IL films exhibited high anisotropic thermal conductivity (K ∥ of 8.3 and K ⊥ of 0.8 W m−1 K−1), outstanding thermal stability and flame retardancy with a dramatic decrease in PHRR (104.2 W/g) and THR (8.1 kJ/g) corresponding to reductions of 72.9% and 75.7% compared with neat EP, respectively. Additionally, the flat oriented structure and strong interfacial interaction also endow EP/BNNS@IL films with high flexibility and excellent mechanical properties. Therefore, the high-effective CLbL casting method and the obtained high-performance EP-based film exhibit a significant potential application in high power flexible electrical devices and thermal management products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Slightly crosslinked PVDF is prepared by γ-ray irradiation. • Piezoelectric film is fabricated by melt stretching of slightly crosslinked PVDF. • The film shows high optical transmittance and also superior mechanical properties. • Ultrahigh content of electroactive β-phase is obtained with aligned nanofibrils morphology. • Excellent sensing performances of film are demonstrated by serving as a wearable sensor. Flexible, transparent and lightweight polymer piezoelectric films are promising for emerging sensor applications, including wearable electronics and human–machine interfaces. However, it remains a great challenge for large-scale fabrication of high-quality polymer piezoelectric films by a cost-effective melt processing approach, mainly due to the difficulty of acquiring well-defined electroactive phases. Herein, a readily implementable and scalable strategy is reported to achieve poly(vinylidene fluoride) (PVDF) film with ultrahigh content of electroactive β-phase (∼96%) via melt stretching of slightly crosslinked PVDF. Upon controlled temperature and stretch ratio, the β-phase adopts an oriented nanofibril (diameter, 21.6 nm) morphology, while nanofibrils are further densely and parallelly aligned to fill the film space. The hierarchical nanoscale phase morphology endows the slightly crosslinked film with high optical transmittance (∼90%), good flexibility and also superior mechanical properties. Moreover, flexible piezoelectric device constructed on the film is demonstrated to have excellent electrical output with sensitive and repeatable responses in sensing dynamic pressure (0–250 kPa), temperature variation (3.3 mV oC-1), human motions and subtle physiological activities. This study therefore paves the way towards scalable manufacturing of high-performance piezoelectric polymer film through simple melt stretching. [ABSTRACT FROM AUTHOR]

[Display omitted] • A cost-effective method was proposed to fabricate single-layer polymer actuator. • Such actuator exhibits excellent actuation performance and durability. • Such actuator can further realize programmed deformation. • Soft robots that mimic snake wrapping and frog jumping were successfully constructed. Polymer actuators that can produce programmed deformations upon environmental stimulation (e.g., heat, light, electricity and chemical vapor) have attracted more attention due to their great potential in some emerging fields of soft robots, sensors, biomimetic devices, artificial muscles, etc. Unfortunately, interfacial failure is frequently happened in bilayer or multilayer actuators due to the poor compatibility between their heterogeneous components. Although some reported single-layer polymer actuators are free of such irritating interfacial failure, facile fabrication of such actuators remains a huge challenge. Herein, a facile but cost-effective strategy to fabricate single-layer homogeneous-polymer Janus actuator (SHJA) based on thermoplastic was proposed. With the help of vacuum-assisted hot-press molding, micro-ridge arrays were introduced onto homogeneous polyvinylidene fluoride (PVDF) film surface, enabling such micropatterned surface to swell asymmetrically and bend in controllable direction in acetone vapor. Such SHJA exhibits excellent actuation behaviors and durability. Interestingly, diversely biomimetic motions including wrapping and jumping can be realized, which highlights its promising potential for applications in soft robots, sensors, biomimetic devices and artificial muscles. Moreover, considering the facile preparation process, low-cost and recyclable substrate material, this approach can be easily scaled up for industrial production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon welding is used to reduce filler-to-filler ITR in 3D graphene skeleton. • Introducing the graphene skeleton into PCM improves its thermal conductivity. • The graphene skeleton can avoid the leakage of PCM during solid–liquid phase change. • The graphene skeleton endows PCM with solar-to-heat conversion capacity. Advanced phase change materials (PCMs) with three-dimensional (3D) thermal conductive skeletons reveal the promising prospect in the thermal management of lithium battery. However, the high filler-to-filler interfacial thermal resistance (ITR) arising from the weak interfacial contact connection in 3D skeleton is still challenging. Herein, we demonstrate a "carbon welding" strategy for reducing the filler-to-filler ITR in 3D graphene skeleton by achieving the lattice connection between contact graphene. Typically, the ordered 3D graphene skeleton was constructed by unidirectionally ice template assembling graphene nanoplates (GNP) with the assistance of poly (amic acid) (PAA). Imidization and carbonization treatments were employed to weld the adjacent GNP in 3D skeleton. The similar lattice structure of carbonized polyimide (PI) and graphene can result in the significant reduction of phonon scattering and ITR at these contact areas. After impregnation with polyvinyl alcohol (PEG), the high-performance PCMs with high-efficient phonon transmission expressway were obtained. As expected, the prepared composites reveal the high thermal conductivities with a maximum value of 7.032 W m−1 K−1 at ~11.6 vol% GNP, which is more than two-fold than that of the composite with uncarbonized skeleton. Finite element simulation and nonlinear model analyses confirm that the reduced filler-to-filler ITR in skeleton is the main reason for the improving thermal conductivity. In addition, the presence of 3D graphene skeleton can effectively avoid the leakage during solid–liquid phase change, and significantly improve the shape stability of the PCMs. At the same time, the graphene skeleton can endow the PCM with an excellent solar-to-heat conversion performance, which ensure a wide range of application in actual environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Conductive MXene coated cotton fabric is prepared for wearable pressure sensor. • The pressure sensor shows both high sensitivity and broad sensing range. • The porous and sandwiched architecture accounts for the good sensing property. • The pressure sensor has great potential for human motion detection and E-skin. Flexible wearable pressure sensors have attracted tremendous interest for applications in human health monitoring, electronic skin, artificial intelligence and so on. However, it is still a critical challenge for pressure sensors to simultaneously achieve high sensitivity and wide sensing range while performing well in response time, stability, reliability and wearing comfortability. Here, conductive MXene/cotton fabric was fabricated using the simple dip-coating technique and then sandwiched between polydimethylsiloxane film and an interdigitated electrode for flexible wearable piezoresistive pressure sensor. The abundant hydroxyl groups of cotton fabric and functional groups of MXene were beneficial for the good adhesion of conductive MXene nanosheets onto the entangled fiber networks, constructing effective conductive network. Taking advantage of the excellent flexibility and three-dimensional porous structure of cotton fabric and the special sandwich architecture of the sensor, the MXene/cotton fabric (MCF) based pressure sensor exhibited high sensitivity (5.30 kPa−1 in the pressure range of 0–1.30 kPa), broad sensing range (0–160 kPa), rapid response/recovery time (50 ms/20 ms), excellent stability and long-term durability. Moreover, the MCF based pressure sensor can be employed to detect and distinguish various human health signals, including finger motion, early stage Parkinson's static tremor and wrist pulse. Importantly, E-skin was also designed based on the MCF based pressure sensor for the recognition of different tactile stimuli, exhibiting promising potential in next generation wearable electronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multifunctional and superhydrophobic cellulose composite paper (CCP) is fabricated. • CCP shows a high EMI shielding effectiveness and electrical conductivity. • The superhydrophobic surface is used as the hydraulic triboelectric nanogenerator. • Surface temperature of CCP can reach 140 °C with a applied voltage of 6 V. Cellulose-based materials have attracted tremendous interest recently due to their fascinating merits of renewability, biodegradability, and low cost, holding great promise in electromagnetic protection, clean energy harvesting, and thermal management. However, the simple and effective integration of multiple functions into single cellulose material remains a challenge. Herein, we report the fabrication of a multifunctional and superhydrophobic cellulose composite paper (CCP) via coated MXene modified by in-situ polymerized polypyrrole and PDMS/candle soot on the opposite surface of the paper. CCP exhibits high-performance electromagnetic interference shielding effectiveness (~40 dB) while maintaining high electrical conductivity (1467 S/m). Moreover, the superhydrophobic surface of CCP can be used as the hydraulic triboelectric nanogenerator (H-TENG) to harvest water energy due to the liquid–solid contact triboelectrification and electrostatic induction. The hydraulic triboelectric energy can be captured and released when water droplets drop from a height of 2 cm and roll at a tilt angle of 20°, the output current can reach a peak of 0.8 nA. Furthermore, the surface saturation temperature of CCP can reach 140 °C with a low applied voltage of 6 V enabled by the Joule effect. Thus, CCP holds great potentials in applications of integrated smart electronics, clean energy harvesting, and thermal management. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrostatic absorption and thermal-cladding assist tight bonding of CNT on TPU. • Segregated CNT/TPU composite exhibits EMI SE of 49.4 dB with only 3.7 wt% CNT. • EMI SE and EM wave absorption are improved by introducing a Ag reflection layer. • Asymmetric TPU/CNT/Ag composites possess excellent EMI SE of 79.4 dB and the lowest reflection of 0.54. Absorption-dominated electromagnetic interference (EMI) shielding composites with high shielding effectiveness (SE) and low reflection (R) is of particular interests for next-generation electronic devices, but it remains a great challenge. Herein, an ingenious approach is proposed to develop asymmetric thermoplastic polyurethane (TPU)/carbon nanotube (CNT)/Ag composites comprised of a segregated TPU/CNT composite layer and a conducting silver layer through the combination of electrostatic absorption, thermal-cladding, vacuum-assisted hot compression, and blade-coating methods. By high-speed mixing of charged CNT and TPU granules and vacuum-assisted compression molding, a segregated TPU/CNT composite layer with highly compacted CNT paths is constructed, which provides efficient electromagnetic wave absorption performance. Further introducing a silver coating serves as a reflection layer, resulting in a special "absorb-reflect-reabsorb" course when electromagnetic waves penetrate the asymmetric composite. The synergistic effects contribute to a preeminent EMI SE of 79.4 dB and SE A of 74.8 dB against the X-band at extremely low filler content (3.7 wt% CNTs and 0.04 wt% Ag) of the asymmetric TPU/CNT/Ag composites, which indicates 99.999999% EM waves are attenuated in the propagation process, and SE A contributes 94.2% to the total SE. Moreover, an R-value of 0.54 is reached because of the destructive interference between the reflected and incident EM waves. This work opens an avenue for the design and fabrication of EMI shielding CPCs with reliable absorption-dominated features and is highly promising for applications in next-generation electronic devices. [ABSTRACT FROM AUTHOR]

• The interphase chemistries of Na metal anode are comprehensively discussed. • The progress of Na metal anode regarding interphase engineering chemistries is inductively summarized. • Challenges and outlook for interphase chemistries of Na-metal anode are proposed. Sodium (Na) metal is not only the frequently used counter electrode in half-cell evaluation for Na storage materials, but also the essential anode for emerging room-temperature Na metal batteries (SMBs) in various types such as Na-sulfur, Na-oxygen , and Na-carbon dioxides batteries. Recent research into the Na metal employed in batteries has placed a spotlight on enhancing electrochemical stability of Na metal anode by addressing the problems of undesired dendrite growth and instable solid electrolyte interphase (SEI). Especially, the latter is recognized to be more responsible for performance failure in Na metal anode. Here, this review is focused to summarize the recent advancement of the interphase engineering chemistries of Na metal anode. The main origins of performance failure regarding interphase chemistries are comparatively described in detail, emphasizing that health SEI formed on Na-metal surface has a decisive role in anodic electrochemical behaviors. Subsequently, the representative strategies involved with constructing stable interphase are highlighted including electrolyte modulations, artificial coating and conductive matrix. Finally, future prospects into interphase chemistries of Na metal anode are proposed in the last section. This review will provide a clear figure of the state-of-art status research and the development trend of Na metal anode. [ABSTRACT FROM AUTHOR]

The present work proposes a facile method to fabricate elastic micropatterned array, which can be further assembled into multifunctional interlocked e-skin. The as-prepared e-skin can simultaneously recognize pressure–temperature stimuli, monitor multiple arterial pulses waveform. Moreover, human physiological signals can be real-time wirelessly monitored by a remote mobile phone. • Elastic micropatterened array is fabricated via a cost-effective method. • Interlocked e-skin exhibits superior sensing stability in a wide working range. • Such interlocked e-skin can simultaneously recognize pressure–temperature stimuli. • Such interlocked e-skin can discriminate multiple arterial pulses waveform. • Human physiological signals can be wirelessly monitored by a remote mobile phone. Electronic skin (e-skin) based on elastic piezoresistive sensor is considered to be one of the most important components for future wearable electronic devices, whose performances can be substantially improved by shaping patterned surface. However, most patterned surfaces are generally fabricated via some tedious methods. Obviously, it is still a huge challenge to realize high sensing performance via facile fabrication process. Here, an efficient but facile method named hot-air-gun assisted preparation is proposed, which enable quasi-hemispherical micropatterned array to be directly fabricated on the single-walled carbon nanotubes (SWCNTs)/thermoplastic polyurethane (TPU) film. The interlocked micropatterns can significantly improve the sensing performance of the as-prepared e-skin based on such micropatterned film, endowing it with very fast response time (<46 ms), wide working range (0.055–254.8 kPa) and excellent durability (>20000 cycles). Interestingly, the interlocked e-skin exhibits multifunction to simultaneously discriminate pressure–temperature stimuli. Moreover, it can monitor a variety of human physiological signals (e.g., arterial pulse waveform, voice recognition and human breathing behavior), indicating a promising application in human–machine interaction. Furthermore, the as-prepared interlocked e-skin could be connected to a wireless transmitter for wireless monitoring respiratory rates. Considering the facile preparation process and the low-cost raw materials, this approach can be easily scaled up for practical production. [ABSTRACT FROM AUTHOR]

• BNNS was exfoliated and flame retardant functionalized by one-step ball-milling. • Functionalized BNNS showed a potential in preparing highly flame-retardant PTCs. • Both flame retardancy and thermal conductivity of EP were enhanced by adding BNNS. • The PHRR of composite with 5 wt% BNNS 2 decrease by 60.9% when comparing to pure EP. Boron nitride nanosheet (BNNS) reveals a huge potential in preparing highly flame-retardant polymer-based thermal conductive composite, but is limited by its difficult exfoliation and functionalization. Here, hexagonal boron nitride (h BN) was simultaneously exfoliated and flame-retardant functionalized into BNNS via one-step ball milling process based on the synergetic effect of mechanical shear and chemical peeling of ammonium phosphate and sodium hydroxide. Then the epoxy (EP)-based composites containing h BN or BNNS were prepared by solution blending and program-controlled curing. The possible mechanochemical reaction mechanisms were proposed according to the incorporation of density functional theory (DFT) calculations and chemical structure characteristics. As one of potential applications, the obtained flame-retardant functionalized BNNS (BNNS 1 and BNNS 2) were used as multifunctional additives for fabricating high-performance EP-based thermal conductive composites with excellent flame retardancy. As expected, the obtained EP-based composites containing only 5 wt% BNNS exhibited a superior flame retardancy with a dramatic decrease in the values of peak heat release rate (PHRR), the total heat release (THR), the smoke production rate (SPR) and the total smoke production (TSP) corresponding to 60.9%, 35.7%, 44.3% and 38.8% reductions, respectively, compared to neat EP. The dramatical enhancement in flame retardancy was mainly attributed to the catalytic charring effect and physical barrier action of flame-retardant functionalized BNNS, led to the formation of a compact and robust char layer during combustion to protect the underlying polymer. Simultaneously, due to uniform dispersion and strong interfacial adhesion, the incorporation of BNNS not only increased the thermal conduction paths by increasing specific surface area, but also reduced the interfacial thermal resistance (R b) caused by phonon scattering, leading to an enhancement (312.4% and 397.0%) in the TC of EP/BNNS composites at 30 wt% BNNS 1 and BNNS 2 , respectively. [ABSTRACT FROM AUTHOR]

• A simple approach is proposed to fabricate a Janus-paper with superhydrophobicity/superhydrophilicity. • When the prepared mimosa-like Janus-paper is immersed in water, it bends immediately like mimosa. • Janus-paper can significantly improve the cell biocompatibility. • Superhydrophobic and superhydrophilic surfaces can be used for microdroplet transportation. Janus-materials were processed though different characteristics integrate to achieve important functions which have aroused great interest among the scientific research and industrial applications. However, the facile fabrication of Janus-materials with the attributes of chemical-free, low-cost, and simple process is still a great challenge. Herein, inspired by the mimosa and lotus leaf, a Janus-paper with superhydrophobicity /superhydrophilicity is successfully fabricated by a conjunction of PDMS and candle soot coating. The water and sliding contact angles of the superhydrophobic surface are 162° and 1°, respectively, and it also shows a good antifouling properties and mechanical durability. Additionally, the cell biocompatibility of superhydrophobic surface is significantly improved, holding the potential as a cell culture carrier. Due to the inhomogeneous swelling inside the internal structure, the Janus-paper exhibits a mimosa-like behavior when immersed in water, endowing the actuation of a boat model on the water surface. Moreover, due to the different adhesions, the superhydrophobic and superhydrophilic surfaces can be used for microdroplet transportation and water storage devices. This bio-inspired approach provides a new generic route for fabrication of Janus-paper for potential multifunctional applications. [ABSTRACT FROM AUTHOR]

• Flexible HAMS films with alternant graphene and Ni chains were designed firstly. • High-effective electrons and phonons conductive paths were formed in HAMS films. • HAMS films reveal remarkable EMI shielding and thermal conductivity simultaneously. • Stacking hot-pressing for preparing HAMS films is easy to large-scale application. Flexible polyvinylidene fluoride (PVDF) films with various heterogeneous alternating multilayer structure (HAMS) containing high-aligned graphene nanosheets and Ni nanochains were designed for electromagnetic interference (EMI) shielding and heat dissipation applications. Because of the unique structure and highly aligned nanofillers, effective electron and phonon conductive paths were formed in HAMS films with optimal electrical and thermal conductivity of 76.8 S/m and 8.96 W/mK, respectively. Combining the high electrical conductivity and the synergetic electromagnetic loss, as well as multi-level electromagnetic multireflection, the optimal HAMS film with thickness of 0.5 mm exhibits a high EMI shielding effectiveness (SE) of 43.3 dB, showing 98.6% increment compared to homogeneous film (21.8 dB), which can further improve to 51.4 dB when increasing the thickness to 0.7 mm. Simultaneously, the highly concentrated and aligned graphene in alternating layers can contribute to the significant improvement in in-plane thermal conductivity of HAMS films with 14.3% and ~1200% increment comparing to the homogeneous film (7.84 W/mK) and pure PVDF (0.69 W/mK), respectively. Considering the outstanding performance and high-efficiency stacking hot-pressing preparation technique, HAMS films with alternating aligned graphene/Ni nanochain layers present a huge potential in practical large-scale application as advanced EMI protection and thermal management materials. [ABSTRACT FROM AUTHOR]

Interface coupling and valence tuning in scalable black phosphorus/phosphide lamellae enable the preferable electrocatalytic properties for efficient overall water splitting. • Scalable synthesis of phosphide/phosphorene heterostructures is demonstrated. • Tuneable valence modulation of Co-P bonding and Co3+/Co2+ couple can be achieved. • Water electrolysis at a low operation η 10 at 1.666 V with good stability can be realized. • Interface-boosted water dissociation is studied by first-principle calculation. The quest for high-efficiency and earth-abundant electrocatalysts replacing precious metals for water splitting is actively pursued for the future of hydrogen economy to wean us off the dependency on fossil fuel. Herein, a moderate catalyst is constructed via the in-situ formation of well-defined CoP nanodots on electrochemical exfoliated black phosphorus (EEBP) nanosheets for overall water splitting. The electro-exfoliation process ensures a high-yield (~85%) preparation of BP nanosheets from bulk BP, prompting the large-scale chemosynthesis of CoP/EEBP heterostructures. It is demonstrated that the Co3+/Co2+ and phosphide state ratios can be elegantly tuned in the CoP/EEBP heterostructure to modulate electron donating/accepting characteristics. As for hydrogen and oxygen evolution reaction (HER/OER), CoP/EEBP heterostructure reveals remarkable electrocatalytic capacity with ultralow overpotentials of only 118 mV and 315 mV at 10 mA cm−2 (η 10) in alkaline media, respectively. Coupled with CoP/EEBP heterostructure for both anode and cathode, the overall water splitting is attested stably with voltage of 1.666 V at η 10 , which is among the best list of BP-based water-splitting electrocatalysts. The basis of the promising electrocatalytic activity is investigated using density functional theory (DFT) calculations. The results indicate that the CoP-BP interface coupling could be able to benefit the electron-transfer and accelerate the adsorption/dissociation of water. The research provides primary comprehension for the electrocatalytic fulfilment of black phosphorus revisited through valence modulation and interface engineering. [ABSTRACT FROM AUTHOR]

• Enhanced piezoresistive performance of piezoresistive sensor was achieved with the assistance of brittle CNC. • The existence of amphiphilic CNC is beneficial for the dispersion of CNT and the improved compression properties. • The flexible piezoresistive sensor could be applied for human motion detection and artificial electronic skin. Recently, piezoresistive sensors with wide response range and high sensitivity are in great demands with the rapid development of flexible electronic industry. To meet the demands, highly compressible waterborne polyurethane (WPU)/carbon nanotube (CNT) composite foam with enhanced piezoresistive performance was designed through incorporating the brittle cellulose nanocrystal (CNC) during the fabrication process. Here, the homogeneous dispersion of CNT with the assistance of amphiphilic CNC and the good interfacial interaction between CNC and TPU endowed the composite foam with improved compression properties. In addition, the brittle CNC/CNT conductive network is easier to be destructed, generating more significant resistance variation and about as high as 2.5 times the sensitivity of composite foam without CNC. As a piezoresistive sensor, it exhibits good compressibility and stable piezoresistive sensing signal in 80% compression strain range due to the porous structure and good elasticity of WPU. Cyclic piezoresistive sensing tests under different compression strains and rates demonstrate the excellent recoverability and reproducibility of the piezoresistive sensor after the initial stabilization process. More importantly, it also displays a fast response time of about 30 ms and good durability and reproductivity over 1000 compression cycles. Finally, the piezoresistive sensor can be successfully applied to detect various human motions (such as vocal cords/cheeks/fingers/wrists/feet movements) and to fabricate artificial electronic skin. The investigation provides an effective strategy for the fabrication of high-performance piezoresistive sensor. [ABSTRACT FROM AUTHOR]

• A flexible CB/TPU foam with a pinnate-veined aligned porous structure was prepared. • The foam can both serve as a flexible strain sensor and an adsorption material. • The foam sensor has excellent sensing discernibility and high sensitivity. • The sensor exhibits superior response stability in a wide sensing range. In this paper, flexible conductive carbon black (CB)/thermoplastic polyurethane (TPU) foam (CTF) with an intriguing pinnate-veined aligned porous structure was fabricated via a unidirectional freeze-drying process. The density, porosity and average pore size of the composite foam are 0.13 g cm−3, 83.7% and 24.9 μm, respectively. CB particles are uniformly dispersed in the skeleton of the as-prepared foam, resulting in a low percolation threshold of 0.48 vol%. The CTF is capable of distinguishing different compressive strain by change of the relative resistance. Its responsive behaviors towards compressive strain present an excellent linear characteristic with a high gauge factor (GF) up to 1.55. In the piezoresistive tests, the CTF shows a fast response/relaxation time (150/150 ms), fascinating recoverability, excellent response stability within a wide workable detection range up to 80% strain (corresponding pressure of 584.4 kPa) and a superior durability (>10000 cycles), which is mainly related to the pinnate-veined aligned porous structure along the orientation direction. The CTF was then assembled as a wearable sensor to monitor various human motions such as arm bending, squatting, tiptoeing, etc., showing good detection performances. The sensor can also deal with water pollution through oil/water separation, suggesting its multifunctionality and promising prospects in complicated situations. [ABSTRACT FROM AUTHOR]

• Multiple synergistic effects were employed to prepare high performance PTCs. • RGO@Ni(OH) 2 with multiple flame-retardant effects was used as synergistic filler. • Synergistic dispersion and bridging connection induce the high heat conduction. • Catalytic, endothermic, barrier effects contribute to the improved fire resistance. The heat shock, thermal aging and fire hazard of induced by delayed heat diffusion in microelectronic devices require a high-efficiency thermal management system with high-performance electronic packaging materials. In this work, the significant thermal conductivity and flame retardancy of polymer-based thermally conductive composites (PTCs) are addressed by multiple synergistic effects of hexagonal born nitride (h BN) and few flame-retardant functionalized graphene. Briefly, a multifunctional hydrophilic graphene-based hybrid containing Ni(OH) 2 nanoribbons and reduced graphene oxide (RGO) was synthesized by two-step hydrothermal process. The resulted RGO@Ni(OH) 2 hybrid and h BN sheets (lateral size of 4.37 ± 1.68 μm and thickness of 80 ± 21 nm) used as synergistic and main fillers, respectively, was simultaneously added into EP matrix. As expected, the binary fillers showed multiple synergistic effects for improving the thermal conductivity and flame retardancy of composites. Typically, the good dispersion and interfacial interaction of RGO@Ni(OH) 2 hybrid in matrix can not only inhibit the stacking aggregation behavior of h BN sheets, but also bridge adjacent h BN sheets, both of which resulted in a high thermal conductivity (2.01 W/mK) of ternary composites with a synergistic increment of 39.4% comparing to EP/ h BN. On the other hand, their synergistic flame retarding effect including catalytic carbonization, endothermic action and barrier effect induced by RGO@Ni(OH) 2 , as well as "tortuous path" effect of h BN sheets, jointly led to the formation of a compact and robust char layer in condensed phase during combustion. As a result, EP/ h BN/RGO@Ni(OH) 2 exhibited a desired flame ratardancy with considerable reductions being seen in peak heat release rate, total heat release and total smoke production, i.e. , 33.5%, 33.8% and 43.0% comparing to neat EP. [ABSTRACT FROM AUTHOR]