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Zinc-air batteries (ZABs) hold immense promise for energy storage due to their potential advantages over existing technologies in terms of electrochemical performance, cost, and safety. Nevertheless, the commercialization of ZABs is still limited by the slow cathode reaction, especially the oxygen reduction reaction (ORR) during discharge and the oxygen evolution reaction (OER) during charging. In the region of the triphase catalyst/electrolyte/gas interface that is decisive for the performance of ZABs, the low utilization of catalytic sites and the lack of oxygen transfer efficiency are the key constraints on the enhancement of performance. Recent advancements have aimed to address these interfacial limitations through innovative microstructure and bioinspired engineering approaches. This review delves into these latest developments, investigating interfacial issues at both the microscopic and mesoscopic levels. Furthermore, we explore the development of a comprehensive theory–structure–function relationship based on the triphase interface, encompassing in-depth understanding, structural considerations, and microenvironmental modulation. Finally, this review identifies the principal challenges, potential opportunities, and prospective avenues for the regulation of triphase interfaces. This review discusses established strategies and promising research directions aimed at further improving the performance of ZABs with the aim of advancing the commercialization of ZABs and paving the way toward clean and sustainable energy storage solutions. [ABSTRACT FROM AUTHOR]

Abstract: This work highlights the usage of short electrospun fibers for the first time for the preparation of homogeneous polymer nanofiber/polymer composites and the improvement in mechanical properties by an order to magnitude compared to as-electrospun long and continuous nanofibers. Dispersions of short electrospun nanofibers can be processed by liquid processing techniques resulting in nanofiber nonwovens similar to electrospun nonwovens but is independent from the demands of the electrospinning process is one of the emphasis of this work. The re-formation of electrospun fiber nonwovens by dispersion casting of short electrospun polyimide (PI) nanofibers and the preparation of homogeneous polymer/polymer nanofiber composite films were selected as representative examples for showing the versatility of short electrospun fibers. The self-reinforced PI/PI-short nanofiber composite films were obtained from mixtures of short electrospun PI nanofibers and polyamic acid after imidization. Significant improvement of 53% and 87% in mechanical properties like tensile strength and modulus, respectively in comparison to the neat PI film was observed by using just 2wt% of short fibers. Parallel experiments were also carried out with long and continuous electrospun PI fibers and amazingly a huge difference was observed. The amount of continuously long fibers required for achieving almost the same strength was much higher i.e. 38wt% in comparison to the 2wt% required of short fibers. [Copyright &y& Elsevier]

• This review summarizes about porous aerogel and sponge composites for EMI shielding. • The mechanisms, material synthesis and EMI shielding applications are discussed. • Some future challenges and prospects on porous EMI shielding composites are given. [Display omitted] Exploring a light-weight electromagnetic interference (EMI) shielding material with high EMI shielding effectiveness (SE) is of great significance to alleviate the growing EMI pollution problem, prevent electronic instruments from the EMI, and protect human health. Recently, porous aerogel and sponge composites with various special nanomaterials instead of traditional bulky metals, have attracted great attentions in the field of EMI shielding, due to their low density, high porosity, high EMI SE, and good structural stability. In this review, the related EMI shielding mechanisms, construction strategies of porous aerogel and sponge composites, their recent advancements for EMI shielding, and possible future challenges and prospects in this area are summarized in detail. We hope that this review will help to promote the development of porous aerogels and sponges in the EMI shielding domain. [ABSTRACT FROM AUTHOR]

In recent years, both natural melanin and their synthetic analogs have attracted increasing attention as an emerging class of bioinspired supercapacitor materials, due to their rich sources, excellent processability, and extraordinary electrochemical performances. Particularly, the inherent heteroatoms and catechol groups within natural melanin and polydopamine (PDA) nanomaterials can promote the total electrochemical activities and surface activation capabilities of the systems. This review strives to summarize the recent advances and highlights of melanin-inspired supercapacitors by focusing on their chemical structures, fabrication methods, working mechanisms as well as various applications ranging from wearable devices, flexible capacitors to supercapacitor separators. Finally, the current challenges of melanin-inspired supercapacitor systems, and future perspectives in the rational fabrication of the new generation of bioinspired supercapacitors are also closely discussed. This review paper strives to summarize the recent advances and highlights of melanin-inspired supercapacitors by focusing on their chemical structures, fabrication methods, working mechanisms as well as various applications ranging from wearable devices, flexible capacitors to supercapacitor separators. [Display omitted] • The chemical structures and working mechanisms of melanin-inspired supercapacitors were systematically summarized. • The representative strategies for the fabrication of melanin-inspired supercapacitors were presented. • Various applications ranging from wearable devices, flexible capacitors to supercapacitor separators were highlighted. • The current challenges and perspectives on the future research directions were closely discussed. [ABSTRACT FROM AUTHOR]

High-performance porous polyimide (PI) monoliths, including PI aerogels, sponges, and foams, have become one of the hotspots in both researching and applications due to their superior properties such as high porosity, outstanding mechanical and thermal stability, low dielectric constant and thermal conductivity. Up to now, various fabricating methods and applicating situations for PI porous monolith materials have been reported. From the viewpoint of molecular chemistry, porous structure construction, as well as the functional modification, the property optimization and adjustment are feasible, endowing PI monoliths with promising potential for different practical applications (e.g. sensors, low-k materials, thermal management, energy field and utilization, absorption and filtration, photonic utilization, etc.). In this review, the recent progress of porous PI monoliths was summarized in detail based on the fabrication methods, functional modifications, as well as multi-functional applications. Besides, the future perspectives of this field were also provided for reference. Apart from presenting an overview of progress made in the field of PI porous monoliths, this review could also be meaningful for those researching topics which have similarity within. [ABSTRACT FROM AUTHOR]

Highlights: [•] Heat-resistant electrospun PBO nanofibers were prepared from precursor OH-PAA. [•] The obtained PBO nanofibers are thermally stable up to 643°C. [•] The obtained PBO nanofibers have excellent mechanical properties. [•] PBO nanofibers have retention of tensile strength and modulus over 80% at 350°C. [•] Such heat-resistant PBO nanofibers could be used in high temperature fields. [ABSTRACT FROM AUTHOR]

Chain-spherical V 2 O 5 /C composites were prepared by using dandelion fibers as bio-templates through a simple vacuum-assisted immersion method, and their microstructure and electromagnetic wave (EMW) absorption properties were investigated. Results indicated that the EMW absorption performance of dandelion fibers is effectively improved by introducing V 2 O 5 and constructing chain-spherical structure. Notably, the minimum reflection loss (RL min) of V 2 O 5 /C composites with a thickness of 2.35 mm is reached −34.05 dB at 17.52 GHz, and the maximum effective absorption bandwidth (EAB) of the composites is up to 7.52 GHz at 2.85 mm. The improvement in EMW absorption performance is mainly ascribed to the synergistic effects of the increased multiple reflections and scattering, enhanced polarization loss and conduction loss, and impedance matching characteristics. The chain-spherical V 2 O 5 /C composites exhibit great potential as promising candidates for high-performance EMW absorbers. • The V 2 O 5 /C composites with a chain-spherical structure are facilely prepared. • The synergy effect of multiple loss mechanisms enhances microwave absorption. • The RL min of −34.05 dB and the widest EAB of 7.52 GHz are achieved. [ABSTRACT FROM AUTHOR]

The development of robust and bioinspired adhesives with excellent performances including fast gel time, low cost, good adhesion strength and stability, and excellent solvent and temperature resistance against harsh environment is urgent for practical applications. In this paper, kinds of natural polyphenolic adhesives have been successfully fabricated via the multiple polyphenol-diisocyanate cross-linking (PDC) reactions between natural polyphenols (extracts) and diisocyanate molecules. Under heating, as-prepared adhesives could effectively adhere onto a wide range of substrates (i.e. PTFE, PET, PMMA, Al, Cu, paper, glass, wood) through hierarchical interactions. Moreover, these adhesives exhibited great adhesion stability against complex solvents and low-temperature environments, whose adhesion strength could remain unchanged after soaking solvents after 30 days, which was conducive to their potential applications in industry and chemical fields, including petroleum, wood, metal, glass, plastics, and rubber adhesion. We believed that this work would provide new strategies towards the preparation of robust adhesives with excellent resistant against various solvents and low temperature for many fields by using naturally occurring building blocks. Natural polyphenolic adhesives were successfully fabricated via the multiple polyphenol-diisocyanate cross-linking (PDC) reactions between natural polyphenols (extracts) and diisocyanate molecules. Under heating, as-prepared adhesives could effectively adhere to a wide range of substrates (i.e. PTFE, PET, PMMA, Al, Cu, paper, glass, wood) through hierarchical interactions. Moreover, these adhesives exhibited great adhesion stability against complex solvents and low-temperature environments, and the adhesion strength could even remain unchanged after soaking solvents after 30 days. [Display omitted] • Natural polyphenolic adhesives were successfully fabricated. • As-prepared adhesives could effectively adhere to various substrates. • These adhesives exhibited great solvents and low-temperature resistance. [ABSTRACT FROM AUTHOR]

Carbon nanotubes microspheres (CNTsM) with porous skeleton and net structure were successfully prepared by a facile method of ultrasonic atomization combined with heat treatment. Dielectric characteristics and electromagnetic wave (EMW) absorption properties within the frequency range of 2–18 GHz of CNTsM were studied. Owing to increased multiple reflection/scattering, enhanced interfacial polarization and optimized impedance matching, an excellent EMW absorption performance is therefore obtained for CNTsM. The maximum reflection loss (RL) reaches −35 dB at the thickness of 4.6 mm, and a wide effective absorption bandwidth (EAB, RL < −10dB) of 4.4 GHz is achieved with a thickness of 1.5 mm. CNTsM can be regarded as a brand-new competitive candidate for EMW absorption materials. [ABSTRACT FROM AUTHOR]

Electrospinning is a common method for preparing nanomaterials. Among many electrospinning materials, electrospun carbon nanofibers (CNFs) have become one of the hot research directions for advanced functional materials owing to their good mechanical properties, high surface area, excellent flexibility, physical and chemical stability. Particularly, significant progress has been made in the engineering advancement of electrospinning, electrospun CNFs and their derived reinforced composites to fulfill various applications. This review aims to afford a comprehensive overview of electrospun CNF reinforced composites. Firstly, the different precursors, the correlative properties, and surface modification strategies (e.g. , physical modification and chemical modification) of electrospun CNFs are introduced. Secondly, the preparation methods of reinforced composites based on electrospun CNFs are described in detail. Then, the functional applications of electrospun CNF reinforced composites are discussed. Finally, the challenges and future solutions of electrospun CNF reinforced composites are also prospected. This review is expected to offer a basic but deep understanding of modification strategies to heighten the surface performances of CNFs for the future development of high-performance electrospun CNF reinforced composites in the composite industry, defense, and aerospace applications. [Display omitted] • Electrospun CNF reinforced composites are widly used in engineering materials. • The precursors and modification strategies of electrospun CNFs are detailly reviewed. • Diverse preparation and application of CNF reinforced composites are summarized. • The current challenges of electrospun CNF reinforced composites are discussed. • The future prospects of CNF-based composites in advanced engineering are proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • The recent progress of electrospun nanofibers as electrocatalysts for flexible metal-air batteries has been reviewed. • The fundamental principles of electrospinning technique have been introduced. • The importance of bifunctional electrocatalysts for oxygen reduction and oxygen evolution in metal-air batteries has been highlighted. • Future perspectives of novel electrospun nanofibers composite for flexible metal-air batteries have been proposed. Rechargeable metal-air (O 2) batteries have been regarded as the promising candidates for wearable and flexible energy devices owing to their outstanding energy density, low cost, and high safety. Generally, the electrocatalyst at air cathode plays a significant role in various metal-air (O 2) batteries. As a versatile and efficient technique, electrospinning has been considered as a powerful method to fabricate nanofibers, which hold great potential as bifunctional electrocatalysts for such batteries. Although great progresses have been achieved in improving the electrochemical performance of catalysts in recent years, some critical challenges still maintain. In this review, the advanced electrospun carbon nanofiber-based electrocatalysts for flexible metal-air batteries have been summarized. Then, additional discussions have been included focusing on the advantages and characteristics of different nanofibers and some special requirements for various flexible metal-air batteries. Moreover, some current challenges and future prospects in the development of electrospun carbon nanomaterials for flexible metal-air cathode catalysts have been rationally analyzed. [ABSTRACT FROM AUTHOR]

With the development of the electronic industry bringing convenience to people, a series of caused electromagnetic pollution problems (e.g., electromagnetic interference (EMI)) have recently also become urgent tasks. In this work, an anisotropic composite sponge consisting of cellulose nanofibrils (CNFs) and chemical co-precipitated silver nanowire (AgNW)@Fe 3 O 4 composites was successfully prepared. Due to the introduction of anisotropic structures and the synergistic effect among CNFs, AgNWs, and Fe 3 O 4 , this composite sponge exhibited low density (16.76 mg/cm3), good saturation magnetization (4.21 emu/g) and electrical conductivity (0.02 S/cm), and anisotropic EMI shielding ability. By adjusting the proportion (1:0.3) between AgNWs and Fe 3 O 4 and their loading (0.15 vol%) inside the sponge, the reflection loss of the sponge with the improved interface impedance mismatch was only 2.3 dB, accounting for 7.2% of the total loss. It is expected to become a promising EMI shielding material, especially for effectively alleviating the secondary reflection EM pollution. [Display omitted] [ABSTRACT FROM AUTHOR]

Although tremendous efforts have been devoted to manganous oxide (MnO)-based hybrid electrode materials, the rational design and facile preparation of high-performance MnO hybrid supercapacitors are still full of challenges, due to the inevitable agglomeration and limited stability of MnO within carbon matrixes. In this work, we developed a direct one-pot polymerization method to synthesize a series of Mn ion doped polylevodopa [P(L- DOPA)] synthetic melanin nanoparticles (Mn@SMNPs) for further transforming into small-sized hybrid carbon nanoparticles (MnO@CNPs, 20–80 nm) consisting of many stable Mn-related chemical bindings (C–N–Mn). The obtained MnO@CNPs electrode materials with physically spatial protection and well distribution of MnO could display high specific capacitance values (e.g., 545 F g−1 at 0.5 A g−1 in 6 M KOH electrolyte) within a wide operation voltage of 1.3 V. This work will continue to provide an inspiration towards the fabrication of the next-generation of high-performance synthetic melanin-based energy storage materials and devices. [Display omitted] ● MnO@CNPs were prepared through a facile one-pot fabrication strategy with small size and high MnO doping content. ● The obtained MnO@CNPs with physically protection showed a well distribution of MnO. ● The stable C–N–Mn chemical binding structure facilitates the stabilization of MnO during the charging and discharging. [ABSTRACT FROM AUTHOR]

Magnetic composites had attracted considerable attention owing to their outstanding properties in separation techniques. In this work, Fe 3 O 4 @polydopamine-g- l -cysteine (Fe 3 O 4 @PDA-g-L-Cys) core-shell composites were successfully fabricated via dopamine self-polymerization and zwitterionic cysteine covalent graft, aiming for removing Pb2+ from an aqueous solution. The structure and morphology of Fe 3 O 4 @PDA-g-L-Cys were verified by FT-IR, XRD, TEM and SEM. The factors (pH, adsorbent dosage, temperature, initial concentration, etc.) affecting the adsorption properties were systematically evaluated. Adsorption data were expressed by the Langmuir isotherm. The kinetic date of Fe 3 O 4 @PDA-g-L-Cysadsorbent for Pb2+adsorptionfitted the pseudo-second order kinetic model well. The obtained thermodynamics constantsΔ G 0, Δ H 0, and Δ S 0 indicated that process of Pb2+ removal by Fe 3 O 4 @PDA-g-L-Cys were endothermic and spontaneous. • A controllable strategy to prepare Fe 3 O 4 @PDA@L-Cys was presented for the first time. • The factors affecting the adsorption properties were systematically evaluated. • Fe 3 O 4 @PDA@L-Cys exhibited high adsorption capacity to Pb2⁺ and excellent recyclability. • The thermodynamic properties of adsorption behavior of Fe 3 O 4 @PDA@L-Cys were studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of electrode thickness on the supercapacitance performance is studied. • Bass wood with hierarchical pores is easy processed to thick electrode. • The thick electrodes have high specific/areal/volumetric energy/power densities. • The SSC shows excellent cycling performance of 81% (20 mA cm−2, 15 000 cycles). The practical application of energy storage device requires high areal/volumetric energy density. One of the strategies is to design bulk electrode with hierarchical porous structure for the application of supercapacitor. Significantly, the energy storage electrochemical performance of the bulk electrode is highly influenced by the pore structure regulation and electrolyte infiltration. Therefore, it is necessary to design thick electrodes with proper pore structures and investigate the effect of thickness on the supercapacitance performance. In this work, bass wood is selected as the carbon source of electrode because of its hierarchical porous structure and easy processing into different thicknesses. The wood-derived carbon thick electrode with a thickness of 1.532 mm (CWT1.532) presents the best supercapacitance performance. Such electrode possesses a high active material loading of 54.75 mg cm−2. The symmetrical supercapacitor from CWT1.532 electrode displays remarkable specific capacitance of 65 F g−1 and areal/volumetric capacitance of 0.846 F cm−2 and 2.67 F cm−3 at 1.0 mA cm−2, respectively. It also exhibits mass/areal/volumetric power densities of 38.47 W kg−1, 500 mW cm2 and 1580 mW cm−3 as well as the corresponding energy densities of 9.04 Wh kg−1, 117.5 mWh cm−2 and 0.374 mWh cm−3, respectively. Moreover, the symmetrical supercapacitor shows an attractive cycling stability with a supercapacitance retention of 81.48% at 20 mA cm−2 even after 15 000 long-term cycles. This work provides an essential understanding about the effect of different thicknesses on the thick electrode-assembled supercapacitance and inspires future practical application in other energy storage areas. [ABSTRACT FROM AUTHOR]

Metal-phenolic networks (MPNs) which integrate the benefits from natural phenolic molecules and metal ions have widely emerged as versatile coating materials in various fields. Although a wide range of MPN utilizations from biomedicine to environment has been well documented, the use of MPNs in the field of flame retardant is still in the infancy. To achieve this goal, tannic acid (TA)-FeIII MPNs as highly efficient and green flame retardant was designed to coating on the surfaces of polyurethane (PU) foams. Due to the excellent carbonization, superior free radical scavenging ability of TA, and condensed-phase action provided by FeIII for catalysing the charring process during combustion, the MPNs coated PU foams could achieve promising flame retardancy performances. Further investigations also indicated that the coated TA-FeIII MPN could successfully inhibit the release rate and total amount of heat and smoke, and the volatilization of harmful gases during the combustion process had also been successfully reduced. This study illustrates a promising and green strategy towards the surface engineering of many substrates by MPNs coating for flame-retardant applications. [Display omitted] • An efficient and green strategy for preparing flame-retardant coatings using metal-phenolic networks. • Excellent carbonization and superior free radical scavenging ability leading promising flame retardancy performances. • The simple surface modification well preserving the mechanical properties of composite materials. [ABSTRACT FROM AUTHOR]