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Photothermal membrane distillation (PMD) achieves localized temperature increase by absorbing and converting light energy to drive evaporation and phase change processes. It is expected to solve the challenges of low energy conversion efficiency and fouling of traditional membrane distillation (MD). A dual-structured photothermal composite membrane was constructed by oxidatively polymerizing photothermal functional materials on an electrospinning substrate membrane. The superhydrophobic Polytetrafluoroethylene/Polyimide (PTFE/PI) substrate membranes offer a spacious pore structure and excellent mechanical properties with low mass transfer resistance and low heat loss. The presence of the densely connected region of the Polyaniline (PANI) in the photothermal layer accelerates the local photothermal conversion. The porous structure formed by interconnecting fibers loaded with PANI is conducive to the repeated refraction of light beams and thus enhances the absorption of light energy. Under 1 kW·m−2 light intensity, the permeate flux of the PTFE/PI-PI/PANI membrane is stable at 1.44 ± 0.02 L·m−2·h−1 within 480 h PMD. With the outstanding salt rejection performance of 99.99 % and high photothermal conversion efficiency of 90.3 %, the photothermal membrane can be applied in areas where fresh water and fuel resources are scarce but solar energy resources are abundant. [Display omitted] • The superhydrophobic layer prevents membrane wetting for durable PMD operation. • The hydrophilic photothermal layer mitigates the temperature polarization effect. • The dual heating mode of composite membrane boots the mass transfer driving force. • The overall porous structure expands efficient water vapor transmission channels. [ABSTRACT FROM AUTHOR]

• Electrospun membranes are innovatively used for anode surface modification. • One-piece modified zinc anode with a strong bonding interface is constructed. • Hydrophobic but cation-selective modified layer is successfully constructed. • The inhibition of side reaction and regulation of ion transport by P-N@Zn are proved. • P-N@Zn has excellent cycling performance and corrosion resistance. Interfacial side reactions triggered by aqueous electrolytes and the growth of dendrites are urgent problems in the field of aqueous zinc ion batteries. This study introduces a novel modification layer for zinc anodes in aqueous zinc ion batteries (ZIBs). The layer, named PCL-Nafion@Zn (P-N@Zn), combines hydrophobic properties (from PCL) with cation selectivity (from Nafion). This combination effectively tackles common issues in ZIBs, such as dendrite growth and water-related side reactions. While Nafion as the filler is enriched with sulfonic acid groups, which promote the transport of zinc ions and facilitates the formation of smooth Zn deposition layer. Benefiting from the effective protection, the PCL-Nafion@Zn||Cu cell has a high Coulombic efficiency (99.3 %) at 2 mA cm−2, and the symmetric cell has a stable cycling of more than 2,900 h at 1 mA cm−2. Have a good cycling stability at high current densities. In addition, the full cell maintains a residual capacity of more than 90 mAh/g after 500 cycles at 1 A/g, which is superior to bare Zn and Nafion@Zn cells. [ABSTRACT FROM AUTHOR]

A high-performance proton exchange membrane was successfully prepared by incorporating an interconnected PMIA nanofiber@ZIF-8 network (ZHNFs) into Nafion solution, in which the unique ZHNFs were fabricated via in-situ growth of ZIF-67 on the surface of hierarchical PMIA nanofibers (HNFs) with multiscale nanofibers and high hydrophilicity. The hybrid membrane presents an outstanding performance with a peak proton conductivity of 0.277 S cm−1 at 80 °C, 100RH% and a decreased methanol permeability of 1.415 × 10−7 cm2 s−1, implying a promising application in direct methanol fuel cells. The superior performance of the membranes could be due to the interconnected structure, high specific surface area of 122.637 m2 g−1 and active chemical bond of (−N–H) of ZHNFs. Specifically, the 3D interconnected structure of ZHNFs provides consecutive conduction path for protons, ensuring the improvement of proton conductivity. The effective interfacial acid-base pairs (−N–H ... −SO 3 H) formed via the tight interactions between the –N–H bonds in ZHNFs and –SO 3 H groups in Nafion matrix could effectively ameliorate the compatibility of the nanofiber fillers and Nafion matrix, further promoting the methanol barrier of the hybrid membranes. Moreover, the generated acid-base pairs are beneficial for the efficient and rapid proton transfer via providing abundant proton conducting sites. • Interconnected PMIA nanofiber@ZIF-8 network was obtained. • Hierarchical proton-conducting channels and hindered methanol penetration routs were simultaneously achieved. • Proton conductivity was highly of 0.277 S cm−1 at 80 °C, 100 RH%. [ABSTRACT FROM AUTHOR]

Among the various desalination technologies, membrane distillation (MD) stands out for its high salt rejection, low operating temperature and operating pressure. Photothermal membrane distillation (PMD) represents an innovative approach to membrane distillation (MD), wherein the process harnesses plentiful and renewable solar energy to achieve localized heating at the interface between the membrane and the feed solution. This is achieved by employing photothermal materials, eliminating the need for heating a substantial volume of the feed solution. This study has prepared membranes with micro/nano fiber interwoven structure based on polystyrene (PS) and polyvinylidene fluoride hexafluoropropylene copolymer (PVDF-HFP) by electrospinning technology, and constructed multi-stage MoS 2 photothermal fiber membranes by hydrothermal growth process. The PS/PVDF-HFP micro/nano fiber membrane possesses a spacious pore structure and high porosity, serving as a robust framework that facilitates swift transport of water vapor. The MoS 2 nanoflowers uniformly grown on the micro/nano fibers have both metal 1T and semiconductor 2H phases, which facilitate the absorption of sunlight, reaching an average absorbance of 90.9 % in the240-2600 nm wavelength range. Under 1 kW m−2 solar illumination, the surface temperature of the PS/PVDF-HFP/MoS 2 membrane could be raised to 74.2 °C after 120 s. The permeate flux was stable at 1.21 ± 0.02 L m−2 h−1 within 20 h PMD. The membrane showcased a salt rejection rate of 99.96 % and achieved an energy efficiency of 72.08 %. This suggests that the multi-stage MoS 2 photothermal fiber membrane, characterized by remarkable stability and high photothermal conversion efficiency, lays a solid foundation for advancing research in the field of PMD applications. [Display omitted] • Construction of electrospinning multi-stage fiber membranes loaded with MoS 2. • Membranes feature large pore size, high porosity and high photothermal efficiency. • Multi-stage fiber membranes are used for brine purification. • Photothermal membrane distillation process runs with high flux and salt rejection. [ABSTRACT FROM AUTHOR]

Recently, Li-ion capacitor as a kind of novel energy storage device with high energy density and power density have caused wide concern. In this study, the porous carbon nanofiber/molybdenum disulfide nanoflake-flowerballs composite material is successfully prepared via hydrothermal method using the three-dimensional porous carbon nanofibers as a carrier. The molybdenum disulfide nanoflake-flowerballs are uniformly distributed and fill in three-dimensional porous carbon nanofibers skeleton, and the clear composite material with nanofiber morphology is formed. This material presents moderate specific surface area (81.67 m2 g−1) and good electrical conductivity (22.32 S cm−1) and is used as the anode in the Li-ion capacitor, and the big energy density at high power density (the energy density could reach 75.5 Wh kg−1 and 22.5 Wh kg−1 at power densities of 0.075 kW kg−1 at 30 kW kg−1, respectively) are achieved, which has broad application prospect in the energy storage field. • The three-dimensional PCNF loading MoS 2 nanoflake-flowerballs was constructed. • The MoS 2 nanoflake-flowerballs inner nanofibers provide the large reaction area. • The three-dimensional PCNF skeleton offers conductive path. • The 3D-PCNF/MoS 2 -NFFBs used as the anodes of LICs exhibit excellent properties. [ABSTRACT FROM AUTHOR]

Li-ion capacitor as a kind of new-style energy storage devices has attracted growing attention due to its high power and energy density. In this study, the stereoscopic honeycomb-like porous carbon nanofiber (PCNF) was used as a carrier of TiO 2 nanoparticles via simple immersion and calcination. The equally distributed anatase TiO 2 nanoparticles filling in the stereoscopic honeycomb-like PCNF skeleton provided large reaction sites, and the stereoscopic honeycomb-like PCNFs acting as support materials offered shorter electrical paths. The composite material presented unique fiber morphology, high specific surface area (268.32 m2g-1) and preferable electrical conductivity (1.31 S cm−1) which was used as an anode in Li-ion capacitor, and the large energy density versus power density (69.46 Wh kg−1 at 0.15 kW kg−1, 18.33 Wh kg−1 at 30 kW kg−1) and good cycle stability (retains 79.4% after 4000 cycles at 1 A g−1) were achieved, which had broad application prospect in the energy storage field. • A stereoscopic honeycomb-like PCNF loading TiO 2 nanoparticles material is designed. • The TiO 2 nanoparticles uniformly distribute and fill in stereoscopic carbon skeleton. • The stereoscopic honeycomb-like PCNF skeleton offers electrical conductivity to TiO 2. • The LIC with TiO 2 @PCNF anode exhibits good electrochemical properties. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Carbon nanofibers with hierarchical pore structure (HPCNFs) were applied as conductive matrices to hybridize with red P. • Red P were embedded in HPCHFs with a homogeneous and sufficient distribution. • P-HPCNFs anodes exhibited promising electrochemical performance. Abstract Red phosphorus (P) with high theoretical capacity and cost-efficiency shows tremendous potential as high-performance anode material. Here, we designed hierarchical porous carbon nanofibers (HPCNFs) by electro-blown spinning of polyvinyl alcohol/polytetrafluoroethylene (PVA/PTFE) with following carbonization and then encapsulated P into this HPCNFs via vaporization-condensation. The P-HPCNFs anodes presented a promising cyclability with reversible capacity of 883 mAh g−1 after 100 cycles and rate performance of 606 mAh g−1 at 1 A g−1. The improvement of electrochemical performance for P-HPCNFs could result from unique nanostructure, in which HPCNFs ensured not only the high conductivity of electrons but also the stable structural integrity. Additionally, the designed hierarchical pore structure with sufficient surface area well accommodated the volume change and highly facilitated the access of electrolyte to active P. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • One-dimensional C/Ce-compound (CeF 3 and CeO 2) composite materials were successfully designed. • CeF 3 and CeO 2 nanoparticles were uniformly dispersed in the porous nanofiber framework. • The porous nanofiber skeleton was beneficial to overcome the drawbacks of nanoparticles. Abstract For practical application of Ce material, one-dimensional C/Ce-compound (CeF 3 and CeO 2) composite materials were successfully designed. Carbon skeleton with unique interconnected porous structure and high specific surface area were manufactured by electro-blown spinning method, using polyvinyl pyrrolidone as the carbon precursor and polytetrafluoroethylene as the pore forming agent. CeF 3 and CeO 2 nanoparticles were uniformly doped in PCNF framework by in-situ encapsulation and hydrothermal methods, respectively. The porous nanofiber skeleton was beneficial to overcome the agglomeration and recycling problem of Ce-compound nanoparticles. This designed structure provided a promising strategy to ameliorate nanostructure material, suggesting potential application in catalyst and energy storage system. [ABSTRACT FROM AUTHOR]

Herein, the composite carbon material of porous carbon nanofiber and carbon nanotube is developed via electro-blown spinning and one-step simultaneous carbonization and chemical vapor deposition without injecting every kind of reaction gas in proportion and removing catalyst in secondary processing. The carbon nanotubes are uniformly growing on carbon skeleton which dramatically improve the performances such as specific surface area (from 334.066 to 644.589 m2 g−1) and electrical conductivity (from 42.22 to 146.20 S cm−1) comparing with porous carbon nanofibers. The different spinning parameters are investigated to optimize parameters, and the porous carbon nanofiber and carbon nanotube are studied and used as electrode for supercapacitors. The results showed that it possesses excellent electrochemical properties, including high specific discharge capacity (216.5 F g−1 at 1.0 A g−1) and good cycle performance (retains ~ 98.68% after 5000 cycles). Moreover, the convenient one-step prepared method special throughout pores structure and superior performance provide a novel approach for designing new types of carbon composite materials which also possess potential application prospect in fields of catalyst, adsorption, etc. [ABSTRACT FROM AUTHOR]

Abstract 'Corn-on-the-cob' structured ZnS nanoparticles anchored on porous carbon nanofibers (ZnS/PCNFs) were rationally designed and prepared using preoxidized PVA/PTFE nanofibers as porous matrix precursors through subsequent solvothermal and carbonization. The obtained ZnS/PCNFs composite as anode material for lithium ion batteries exhibit a promising cycling performance with high reversible capacity of 718 mAh g−1 at 0.2 A g−1 after 150 cycles and excellent rate capability with discharge capacity of 438 mAh g−1 at 2 A g−1. The prominent battery performance of ZnS/PCNFs electrode might be ascribed to the distinct hybrid structure, where the uniformly arranged nanosized ZnS 'corns' endowed the hybrid with excellent lithium capacitive performance, and the rationally designed PCNFs 'cob' with large specific surface area not only improved the conductivity but also enhanced the diffusion of electrolyte and ion movement within the hybrid. Graphical abstract Unlabelled Image Highlights • Porous carbon nanofibers were introduced as conductive matrices to hybridize with ZnS. • ZnS nanoparticles were uniformly anchored on porous carbon nanofibers with a unique 'corn-on-the-cob' structure. • The composites exhibited exceptional electrochemical performance. [ABSTRACT FROM AUTHOR]

Superhydrophobic waterproof-breathable membranes, which possess a huge superiority in multi-functional applications including self-cleaning, anti-icing, anticorrosion and protective clothing, have aroused considerable attention owing to their excellent performance. Herein, the robust superhydrophobic microporous fibrous membranes were efficiently prepared via a facile and environmental-friendly electro-blown spinning (EBS) technique followed by calcination. Compared with hydrophobic pure PTFE fibrous membranes, the bead-like SiO 2 @PTFE nanofiber membranes (BLNFMs) exhibited superhydrophobic surface with the advancing water angle (θ adv ) and the water contact angle (WCA) up to 161° and 155°, respectively. The SiO 2 nanoparticles were introduced as fillers which can alter the pore structure and form the multilevel rough surface. The BLNFMs could maintain superhydrophobic surface even after abrasion for 30 times or exposing to a strong corrosive solution with PH from 0 to 12 for 24 h. Besides, the BLNFMs were endowed with the modest vapor permeability (9.7 kg·m −2 ·d −1 ) and air permeability (7.2 mm·s −1 ) when the concentration of SiO 2 nanoparticles reached to 7.3 wt%. In addition, a potential relationship among θ adv , maximum pore size (d max ) and breathability (effective breathing area) was proposed in order to design the waterproof-breathable membranes with excellent properties. Furthermore, the superhydrophobic membranes with durable self-cleaning property provided the advantages of potential applications in the fields of membrane distillation, versatile protective clothing, etc. [ABSTRACT FROM AUTHOR]

In this study, the MnO 2 & carbon composite porous nanofibers (CPNF) were prepared via electro-blown spinning and in-situ hydrothermal synthesis. The MnO 2 nano-sheets were uniformly growing on carbon skeleton and filling in honeycomb-like carbon porous nanofibers, and the clear CPNFs were formed. The different hydrothermal parameters including the mass ratios of honeycomb-like porous carbon nanofiber and potassium permanganate, hydrothermal times and temperatures were discussed to obtain optimizing reaction conditions. The CPNFs were investigated by scanning electron microscopy (SEM), transmission electron microscope (TEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and low temperature nitrogen adsorption, respectively, and the supercapacitor performance of CPNF was preliminary tested. The discharge capacity was 421.5 F g −1 at 0.5 A g −1 , and it retained ∼81.2% after 3000 cycles at the current densities of 1.0 A g −1 . Moreover, this CPNF owned special structure and a great industrialization potentiality which could realize the applications in absorption and catalyst fields. [ABSTRACT FROM AUTHOR]

Recently, the multi-level structure materials with some superior performances has attracted broad attentions. In this study, the elastomeric tree-like thermoplastic polyurethane (TPU) nanofiber membranes with multilevel structure were prepared by introducing tetrabutylammonium chloride (TBAC) via one-step electrospinning. The coverage rate and average diameter of the TPU tree-like nanofibers could be controlled by varying the solution concentrations and electrospun parameters. The special multilevel structure with trunk fibers (diameter 300–500 nm) and branch fibers (diameter 20–80 nm) significantly improved crystallinity, hydrophilicity and flexibility performances comparing with pristine TPU nanofibers, and the novel hierarchical elastomeric tree-like nanofiber membrane had a bright future in various potential applications, such as medical, filtration and protective field, etc. [ABSTRACT FROM AUTHOR]

The PVA-based carbon nanofibers with honeycomb-like carbon porous structure were successfully prepared by electro-blown spinning (EBS), pretreatment and carbonation processes. PVA was used as the carbonized polymer while PTFE was used as the sacrificial polymer. The carbon nanofibers with various pore sizes and distribution were prepared by varying the amount of PTFE loading in the spinning solution and optimizing carbonized parameters. The honeycomb-like carbon nanofibers were investigated by scanning electron microscopy (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectrum and low temperature nitrogen adsorption. It was found that specific surface area and pore volume could reach 591.33 m 2 g −1 and 0.58 cm 3 /g, respectively, and large amount of micro-, meso- and macro-pores existed in this kind of porous carbon fiber when the PVA/PTFE was 1:15. This porous carbon nanofiber with special structure and high yield may realize the applications in the fields of adsorption, ion exchange, catalyst supports, etc., and the prepared method has a great industrialization potentiality. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrospinning hydrophilic/hydrophobic photothermal membranes for SDMD is proposed. • The membrane shows strong photothermal conversion properties and anti-fouling properties. • The membrane exhibits superstable and high flux in long-term desalination of SDMD. Low permeate flux and membrane fouling are major limiting factors for solar-driven membrane distillation (SDMD) industrial applications. Here, we report a Janus nanofiber membrane with electrospinning CB/PVA as hydrophilic photothermal layer and electro-blown spinning PTFE nanofiber membrane as hydrophobic layer, which exhibits excellent photothermal conversion performance, anti-fouling performance and durability. The hydrophilic photothermal layer simultaneously captures solar energy and performs photothermal conversion, repels chemical/oil-based pollutants and promotes steam flow. At the same time, the low surface of PTFE layer can guarantee the long-term durability of the composite nanofiber membrane. Under the light intensity of 1 kW·m−2, the Janus nanofiber membrane can obtain a permeate flux of 1.05 L·m−2·h−1 and a salt rejection of > 99.99 %. And the photothermal conversion efficiency reached 71.4 %. More importantly, the permeate flux of the Janus nanofiber membrane was still stable at 1.035 L·m−2·h−1 after continuous treatment of pollutant-containing feed solutions for 60 h, and the salt rejection was > 99.98 %. This indicates that the efficient photothermal conversion performance and anti-fouling properties make the CB-PVA/PTFE photothermal nanofiber membrane promising for generating fresh water from feed solutions containing various pollutants in SDMD systems. [ABSTRACT FROM AUTHOR]

As a kind of high-performance fiber, PTFE fiber has been widely used in many fields because of its unique characteristics. In this study, pure PTFE nanofiber film was prepared effectively through electro-blown spinning (EBS) under dual forces of high speed air flow and static electric method followed by a thermal treatment process. The effects of PTFE/PVA ratio, the amount of boric acid (BA), air pressure, applied voltage and sintered temperature were discussed to obtain the PTFE nanofibers with different diameters, and the film had been characterized by SEM, TG, XRD and XPS, respectively. The results showed that pure PTFE nanofiber film with good morphology could be large scale prepared through the EBS process. Moreover, this novel EBS method may realize the industrialized production of high performance polymer fibers. [ABSTRACT FROM AUTHOR]

Membrane distillation (MD) is an attractive membrane process for seawater and brine water desalination. One of the main obstacles for MD application is the absence of an effective MD membrane with high water permeability and an excellent salt rejection. This work proposes a novel design strategy of hydrophobic/hydrophilic bi-component membranes for MD by electrospinning and calcination. Unlike the conventional dual-layer hydrophobic/hydrophilic membranes, the bi-component membrane developed in this work is composed of multiple layers of hydrophilic polyimide (PI) nanofibers and hydrophobic polytetrafluoroethylene (PTFE) microclusters, which interweave with each other in the entire membrane. The optimal hydrophobic/hydrophilic bi-component membrane #PTFE/PI-2 shows robust three-dimensional (3D) superhydrophobic and self-cleaning properties. It exhibits a highly competitive permeation flux of 42 ± 3 L m−2 h−1 and an excellent salt rejection above 99.9% in a 400-h continuous DCMD operation when the feed solution was synthetic seawater with a NaCl concentration of 3.5 wt% at 60 °C. Moreover, it is able to achieve an outstanding water flux of 40 ± 2 L m−2 h−1 and a salt rejection over 99.9% when the feed solution was brine water with a NaCl concentration of 25 wt%. The high vapor permeability of #PTFE/PI-2 should be attributed to the high membrane porosity, negligible mass transfer resistance of PI nanofibers and more effective water evaporation area on its superhydrophobic surface. Meanwhile, the excellent anti-wetting property should be due to a unique 3D superhydrophobicity constructed by multiple layers of PTFE microclusters. Image 1 • Hydrophobic/hydrophilic bi-component membrane is proposed. • It composes of PTFE microclusters and PI nanofibers. • The resultant membrane exhibits robust 3D superhydrophobicity. • #PTFE/PI-2 shows a water flux of 40 ± 2 L/m2·h and a salt rejection above 99.9% in MD. [ABSTRACT FROM AUTHOR]

Membrane distillation (MD) is an attractive thermally-driven membrane process for desalination, brine and wastewater treatment. One of the main obstacles impeding MD application is the absence of effective MD membranes with sufficient water permeability and long-term stability. Attributed to the outstanding hydrophobicity, excellent thermal and chemical resistance, the most ideal polymer to develop MD membrane is polytetrafluoroethylene (PTFE). However, the fabrication of PTFE membranes is challenging due to its poor processability. This work describes a novel strategy to develop superhydrophobic and highly porous PTFE membranes via electrospinning. The hydrophobic nanoparticles 8 vinyl-grafted polyhedral oligosilicone (vinyl-POSS) were firstly incorporated into PTFE nanofibers to promote the crystallization of PTFE nanofiber, enhance nanofiber roughness, and improve membrane mechanical robustness and porosity. The effects of vinyl-POSS concentration, temperature and salt concentration of feed solutions on MD performance of PTFE/POSS nanofibrous membranes were investigated systemically in this study. The optimized PTFE/POSS nanofibrous membrane #POSS-2 has a three-dimensional (3D) superhydrophobic property with a water contact angle of 151 ± 4°. It exhibited a competitive water flux of 40 ± 2 Lm−2 h−1 in the direct contact membrane distillation (DCMD) process when the feed and permeate temperatures were 60 and 20 °C, respectively. Moreover, #POSS-2 possessed an excellent long-term stability in a 200-h continuous DCMD operation. Unlabelled Image • Vinyl-POSS has been incorporated into PTFE nanofibers to promote PTFE crystallization. • PTFE/POSS nanofiber shows a highly rough surface with valleys and ridges. • #POSS-2 possesses 3D superhydrophobicity, high porosity, and sufficient mechanical and chemical robustness. • #POSS-2 shows a competitive water flux and a stable rejection above 99.99% in a 200-h long-term DCMD operation. [ABSTRACT FROM AUTHOR]

In this work, the inorganic-organic nanofibrous composite separators were successfully prepared for Li-ion capacitor (LIC) via wet-laid method using electro-blown spun inorganic alumina (Al 2 O 3) nanofibers and electrospun organic polyimide (PI) nanofibers as components. Benefitting from the synergistic action of fast ions transfer performance and outstanding fire-resistance offered by Al 2 O 3 nanofibers as well as heat-resistance and entangled force derived from PI nanofibers, the novel membranes exhibited excellent film forming property, outstanding flexibility and high ionic conductivity. Moreover, it delivered superior fire-resistance with dimensional stability after burning. It was discovered that the novel membranes prepared with 50 wt% Al 2 O 3 nanofibers showed better ionic conductivity of 2.71 × 10−3 S cm−1 and broader electrochemical stability window of 5.3 V than those of commercial membranes. The LIC assembled with this novel separator reached the energy density of 12.5 Wh kg−1 even at the high power density of 15 kW kg−1. In addition, this LIC presented a high energy density of 57.3 Wh kg−1 at the current density of 0.5 A g−1 and maintained a high cycle stability even after 10,000 cycles. This study provided the design idea and experimental basis for the development of high-performance LIC separator. [ABSTRACT FROM AUTHOR]

• Stearate and hindered amine light stabilizer were compounded as electret additives. • Water electret melt-blown nonwovens with great filtration performance was fabricated. • The excellent durability was proven through various tests. • Surface friction and ion migration mechanisms were elucidated. • The good charge stability at high temperature and humidity was verified. Water electret (WE) technology is a current research hotspot in the field of high-efficiency and low-resistance melt-blown filter materials. The electret is an important factor affecting the filtration performance and durability of WE melt-blown nonwovens. In this paper, WE melt-blown nonwovens were prepared with stearate compounded with hindered amine light stabilizer (HALS) as the electret additives, which exhibited excellent performance and the filtering efficiency of DEHS oily particles exceeding 99%. The charge formation and storage mechanism of WE melt-blown nonwoven were also elucidated by using the thermally stimulated discharge technique. Benefiting from the inherent amino group of HALS and the synergistic effect with stearate, positively charged hydrated protons were attracted and migrated to the interior of the fiber to form durable space charges, which led to a significant enhancement of the filtration/charge storage performance of melt-blown nonwoven. The charge stability performance of WE melt-blown nonwoven was also investigated under the treatment of solvents such as constant temperature and humidity, high-temperature hot water, alcohol, and isopropyl alcohol. These studies help to improve the product quality of WE melt-blown nonwovens, as well as provide a systematic guide to an in-depth understanding of the electret mechanism of WE technology. [ABSTRACT FROM AUTHOR]

Abstract In this study, a novel core-shell structured poly-m-phenyleneisophthalamide@polyvinylidene fluoride (PMIA@PVDF) nanofiber separator was successfully synthesized via facile coaxial electrospinning. The thermal resistance, electrolyte uptake, ion conductivity as well as anodic stability window of the nanofiber separator were synchronously improved to above 260 °C, 753%, 1.7 mS cm−1 and 5.0 V, which resulted in an appealing safety and electrochemical performance. The markedly enhanced performance could be ascribed to the synergistic advantages of the PMIA core and PVDF shell in the homogeneous PMIA@PVDF nanofiber separator. The PMIA core in PMIA@PVDF nanofiber with high melting point and rigidity character acting as stable skeleton strengthened the thermal stability and integrity of the whole separator. Meanwhile, the lyophilic PVDF shell along with the interconnected open pore structure of electrospinning membrane guaranteed the membrane wettability to electrolyte so as to the ion conduction. Most impressively, under high temperature treatments above 180 °C, the PVDF shell could melt and completely occlude the macropores in PMIA@PVDF nanofiber separator to shut down the battery operation without obvious dimensional shrinkage. Thus, the superiorities in electrochemical performance and safety made PMIA@PVDF nanofiber separator a highly qualified separator for high performance lithium ion battery. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Highlights • A novel electrospun PVDF-HFP/PMIA nanofiber membrane is successfully prepared. • The membrane can be acted as matrix for heat-resistant gel polymer electrolyte. • The separator has outstanding electrolyte uptake, thermal stability and strength. • The separator possesses high ionic conductivity and stable electrochemical window. • The assembled battery shows high safety and excellent electrochemical properties. Abstract In this work, a novel nanofiber composite membrane constituting poly (vinylidene fluoride-co-hexafluoropropylene) / poly-m-phenyleneiso-phthalamide (PVDF-HFP/PMIA) was successfully fabricated through one-step electrospinning technique. The PVDF-HFP/PMIA nanofibers possessed low average diameter and uniform diameter distribution, which were able to be acted as matrix for gel polymer electrolyte. Significantly, the presence of PVDF-HFP endowed PMIA membrane with considerable high electrolyte uptake and porosity, eminent mechanical strength and remarkable thermal shrinkage resistance. Compared with pure PMIA and polyethylene separators, the PVDF-HFP/PMIA separator obtained higher ionic conductivity, lower interfacial resistance and more stable electrochemical window. The Li/LiCoO 2 battery with the prepared separator reflected admirable cycle stability with outstanding first discharge capacity up to 153.8 mAh g−1 at 0.5C rate and superior capacity retention of 88.75% after 100 cycles. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and theoretical capacity, but the rapid decay of capacity is still a huge challenge. Herein, we reported an ingenious design of nitrogen doped carbon nanofibers with honeycomb-like porous structure for the cathode of lithium-sulfur battery which can effectively suppress the “shuttle effect”. The special porous material with three dimensional (3D) interconnected pore structure is beneficial to enhance the adsorption of lithium polysulfides and accommodate the volume expansion of active materials. In addition, the doped nitrogen can not only improve the conductivity of cathode, but also form a strong interfacial interaction to trap lithium polysulfides. Therefore, the battery with the cathode exhibited a high reversible discharge capacity of 1093.9 mAh g −1 and good capacity retention of 76.0% after 300 cycles at 0.5C rate. After acidification, the cycling performance of the cathode could achieve upon 300 cycles with a very low decay rate of 0.027% at 0.5C. [ABSTRACT FROM AUTHOR]

The honeycomb-like hierarchical porous carbon nanofibers (PCNFs)-carbon nanotubes (CNTs)-sulfur(S) composite electrode is successfully desgined and prepared through ball-milling and heating method, in which the PCNFs are carbonized from fibers in the membrane composed of Polyvinyl Alcohol and Polytetrafluoroethylene by electro-blown spinning technology. The prepared PCNFs-CNTs-S composite are regarded as cathode for lithium-sulfur battery. The tailored porous structure and CNTs in the composite facilitate construction of a high electrical conductive pathway and store more S/polysulfides, and the dissoluble loss of intermediate S species in electrolyte can also be restrained because of acidized PVA-based porous carbon nanofibers. Meanwhile, the porous strcucture and CNTs can effectively alleviate volume changes in battery cycling process. Moreover, the presence of LiNO 3 in electrolyte helps the electrochemical oxidation of Li 2 S and LiNO 3 -derived surface film effectively suppresses the migration of soluble polysulfide to the Li anode surface. Therefore, the obtained PCNFs-CNTs-S cathode exhibits excellent performance in Li-S battery with a high initial discharge capacity as high as 1302.9 mAh g −1 , and super stable capacity retention with 809.1 mAh g −1 after 300 cycles at the current density of 837.5 mA g −1 (0.5 C). And the rate capability of PCNFs-CNTs-S electrode is much better than those of CNTs-S and PCNFs-S electrodes. [ABSTRACT FROM AUTHOR]

• The different fabrication techniques of nanofiber materials are summarized. • The functional action mechanisms of nanofibers for inhibiting Li dendrites are reviewed. • Various protection strategies of nanofiber materials to suppress the Li dendrites growth are summarized. • The challenges and prospects of nanofiber materials for Li anode are discussed. Lithium metal batteries (LMBs) are regarded as one of the most promising candidates for next-generation energy storage systems. However, the uncontrolled dendritic lithium (Li) growth lead to low Coulombic efficiency and security issue, thus limiting the commercial applications of LMBs. Owing to the unique nanostructure characteristics, nanofiber materials offer innovative strategies and opportunities to resolve the tricky challenge. A comprehensive review of the fundamental researches and technological developments of various nanofiber materials for LMBs was presented in this paper. The fabrication techniques of nanofibers and several functional action mechanisms for inhibiting dendritic Li were outlined. Then the different protection technologies of nanofiber materials for LMBs to suppress the Li dendrites growth were summarized, which included modifying separators, introducing functional interlayers and constructing novel composite anodes and current collectors. Meanwhile, the electrochemical performances using different strategies of the overall LMBs were discussed. Finally, the current challenges and prospects of nanofiber materials for Li anode were discussed. These discussions and proposed strategies will enlighten thoughts and offer ways to the practical application of LMBs with excellent electrochemical performances in the future. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries have been considered as one of the most promising energy storage candidates due to their high energy density and low cost. However, the low electrical conductivity of elemental sulfur, notorious LiPS shuttle and sluggish redox kinetics bring about fast capacity fade and poor rate capabilities. To solve these problems, herein a modification strategy of functional separator is introduced by coating heterostructured MoP–MoS 2 and porous carbon nanofibers (PCNFs) on the surface of a Celgard separator. Moreover, for the first time, we detailly discuss the effect of the ratio of component (MoP:MoS 2) in the heterostructured MoP–MoS 2 materials on the electrochemical performance. The coating layer exhibits both satisfactory interception ability for LiPS shuttle and fast LiPS conversion ability due to abundant anchoring sites of MoP–MoS 2 heterojunction nanoflowers and shortened lithium ion channel of the prepared PCNFs. Benefiting from these advantages, the assembled Li–S battery with a MoP-50/PCNFs separator exhibits 1090.02 mAh g-1, and high discharge capacity of 884.67 mAh g-1 even after 300 cycles at 1 C. The initial discharge capacity of MoP-50/PCNFs separator at 2 C and 5 C are about 1050.4 and 728.22 mAh g-1, and retains about 698.4 mAh g-1 after 400 cycles and 431.28 mAh g-1 after 500 cycles. The novel work will provide a new strategy by which the modified separator with transition metal phosphides can be applied in the design of high-performance Li–S batteries and shows great potential for practical application. MoP-x/PCNFs modified Celgard separator in Lithium-sulfur battery. [Display omitted] • Preparing Flower-like heterostructured MoP–MoS 2. • Designing various heterostructured MoP–MoS 2 materials (MoP: MoS 2 = 100:0, 75:25, 50:50, 25:75, 0:100). • Porous carbon nanofiber with dual functions of lithium polysulfudes adsorption through one-step electrostatic blowing method. • Researching the catalytic kinetic mechanism of the "solid-liquid-solid" mutual conversion process for transition metal phosphide. • Exploring the cycle performance of Celgard separator modified with MoP–MoS 2 -50/PCNFs. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries have been considered as one of the most promising energy storage candidates due to their high energy density and low cost. However, the low electrical conductivity of elemental sulfur, notorious LiPS shuttle and sluggish redox kinetics bring about fast capacity fade and poor rate capabilities. To solve these problems, herein a modification strategy of functional separator is introduced by coating heterostructured MoP–MoS 2 and porous carbon nanofibers (PCNFs) on the surface of a Celgard separator. Moreover, for the first time, we detailly discuss the effect of the ratio of component (MoP:MoS 2) in the heterostructured MoP–MoS 2 materials on the electrochemical performance. The coating layer exhibits both satisfactory interception ability for LiPS shuttle and fast LiPS conversion ability due to abundant anchoring sites of MoP–MoS 2 heterojunction nanoflowers and shortened lithium ion channel of the prepared PCNFs. Benefiting from these advantages, the assembled Li–S battery with a MoP-50/PCNFs separator exhibits 1090.02 mAh g-1, and high discharge capacity of 884.67 mAh g-1 even after 300 cycles at 1 C. The initial discharge capacity of MoP-50/PCNFs separator at 2 C and 5 C are about 1050.4 and 728.22 mAh g-1, and retains about 698.4 mAh g-1 after 400 cycles and 431.28 mAh g-1 after 500 cycles. The novel work will provide a new strategy by which the modified separator with transition metal phosphides can be applied in the design of high-performance Li–S batteries and shows great potential for practical application. MoP-x/PCNFs modified Celgard separator in Lithium-sulfur battery. [Display omitted] • Preparing Flower-like heterostructured MoP–MoS 2. • Designing various heterostructured MoP–MoS 2 materials (MoP: MoS 2 = 100:0, 75:25, 50:50, 25:75, 0:100). • Porous carbon nanofiber with dual functions of lithium polysulfudes adsorption through one-step electrostatic blowing method. • Researching the catalytic kinetic mechanism of the "solid-liquid-solid" mutual conversion process for transition metal phosphide. • Exploring the cycle performance of Celgard separator modified with MoP–MoS 2 -50/PCNFs. [ABSTRACT FROM AUTHOR]

In the past few years, biomass carbon materials have gained wide attention from many scholars as TiO2 carrier materials to improve photocatalytic activity due to their renewable, green, low-cost, and high-efficiency advantages. In this study, TiO2/carbonized waste rabbit fibers (TiO2/CRFs) nanocomposites with the hierarchical microporous/mesoporous structure were fabricated by a combination of carbonization, immersion, and calcination methods using tetrabutyl titanate as the titanium source and waste rabbit hair as the carbon source. The properties and catalytic activity of TiO2/CRFs composite were evaluated based on several characterization techniques and methylene blue (MB) photodegradation studies. The results showed that the degradation of MB by TiO2/CRFs could reach 98.1% after 80 min of solar irradiation. Moreover, TiO2/CRFs still maintained high photocatalytic activity after five cycles of degradation tests, exhibiting good stability and reusability. The improved photocatalytic performance of TiO2/CRFs materials is attributed to the natural carbon and nitrogen element doping of TiO2/CRFs and its morphology, which reduces the compounding of photogenerated electron-hole pairs and narrows the TiO2 band gap, while the multiple reflections of visible light in the pore channels enhance the visible light absorption of the materials. Furthermore, the large specific surface area provides abundant reaction sites for adsorbed reactants. This paper provides the experimental basis for the application of waste rabbit biomass carbon composites in photocatalytic degradation field. [ABSTRACT FROM AUTHOR]

Permeability and selectivity are the two most important parameters in membrane distillation process. The membrane with high porosity and superhydrophobicity could increase the mass transfer coefficient, decrease the heat losses and improve the resistance to wettability. To satisfy this purpose, a novel superhydrophobic polyvinylidene fluoride (PVDF)/tetrabutylammonium hexafluorophosphate (TBAHP)/polystyrene (PS) multi-scale nanofiber membrane (MNM) with high porosity and low thermal conductivity was successfully designed and developed via one-step electrospinning. The formation of multi-scale structures was caused by the addition of TBAHP. PS owns low thermal conductivity and low surface energy which can enhance the thermal efficiency and improve the hydrophobicity of MNMs. Besides, the addition of PS can amplify the classifying effect, construct the nano-micron structure and endow the membrane with superhydrophobicity. The results showed that the thermal conductivity of membranes decreased from 0.03361 W/mK to 0.02777 W/mK and the water contact angle increased from 138.2° to 151.7°. The PVDF/TBAHP/35%PS MNMs exhibited a stable MD performance with an average permeation flux of 50 ± 3 L/m2 h and a satisfactory salt rejection higher than 99.9% during 72-h continuous DCMD operation (3.5 wt% NaCl solution, the feed/permeate temperatures were 60/20 °C, respectively). Unlabelled Image • A multi-scale nanofiber membrane (MNM) was developed by electrospinning. • The MNMs exhibited high porosity and narrow pore size distribution. • The MNMs possessed low thermal conductivity and superhydrophobicity. • The MNMs showed high permeate flux (51.96 L/m2 h) and salt rejection (99.99%). [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes replacing traditional liquid electrolytes are considered as an important strategy for developing lithium metal batteries with high safety and energy density. However, poor ionic conductivity and weak mechanical performances have greatly limited the development of solid polymer electrolytes. Here, we dispersed inorganic ceramic particles Li 6 · 4 La 3 Zr 1 · 4 Ta 0 · 6 O 12 (LLZTO) in the polyvinylidene fluoride (PVDF) electrospun nanofibers and then introduced them into polyethylene oxide (PEO) polymers to prepare composite electrolytes. The PVDF nanofibers with embedded LLZTO fillers can simultaneously reduce the crystallinity of the PEO polymer and provide a strong framework support for the composite electrolyte, thereby promoting the transmission of lithium ions and improving the lithium dendrite growth inhibition ability of the composite electrolyte. In addition, the uniform dispersion of garnet-type LLZTO active ceramic filler in the PVDF nanofiber membrane can further optimize the migration path of lithium ions. More importantly, the dehydrofluorination of PVDF due to the introduction of LLZTO can enhance the interaction among PVDF, LLZTO and lithium salts, which promotes dissociation of the lithium salt. The ionic conductivity of the composite electrolyte is as high as 9.30 × 10−4 S cm−1 at 50 °C, and the voltage of Li/Li symmetrical battery would not change significantly during 1200 h at 0.3 mA cm−2. Additionally, the composite electrolytes exhibit good electrochemical stability with the capacity retention rate of 96% under 1 C after 500 cycles. These results provide a strategy for the development of next-generation high-safety all-solid-state lithium metal batteries. An all-solid-state composite electrolyte is synthesized, which has superior ion transmission characteristics, mechanical strength and flexibility, bringing excellent long-cycle stability to Li/Li symmetric battery and Li/LiFePO 4 battery. Image 1 • An all-solid-state composite polymer electrolyte are successfully prepared. • Composite polymer electrolyte exhibits excellent mechanical strength and flexibility. • Li/Li batteries and Li/LiFePO 4 batteries assembled with the composite electrolytes have superior long-cycle stability. [ABSTRACT FROM AUTHOR]

• An all-solid-state root-soil-like composite electrolyte are successfully prepared. • Composite electrolyte present excellent mechanical strength, ionic conductivity and thermal stability. • Composite electrolyte can provide more transmission channels for Li+ ions and inhibit the growth of lithium dendrites. • Li symmetric battery and Li|LiFePO 4 battery with the composite electrolyte present stable long cycle performance and safety. Lithium metal with excellent theoretical specific capacity and low reduction potential is thought as the promising anode material for energy storage device. However, the issues of weak security and poor cycle life resulted from the lithium dendrites growth have greatly limited their quick development. In this study, the electrospun polyvinylidene fluoride (PVDF) nanofiber membrane with multi-level structure was introduced into the polyethylene oxide (PEO) polymer as a nano-polymer filler to construct an all-solid-state root-soil-like composite electrolyte. The mutual overlaps of the coarse fiber and the fine fiber in the membrane provide a strong skeleton support for the electrolyte, and the intermolecular hydrogen bond between the PVDF and PEO can further enhance the interfacial interaction between the membrane and polymer, which in turn make the root-soil-like composite electrolytes have excellent mechanical strength to inhibiting the growth of lithium dendrites. Moreover, the existence of the multi-level structure in the membrane can significantly reduce the crystallinity of the polymer and provide more transmission channels for Li+ ions, so that Li+ ions can be uniformly and rapidly deposited during the plating/stripping process, and the interface compatibility between the lithium anode and electrolyte can be effectively enhanced. The voltage value of the Li symmetric battery can be stabilized at 70 mV for 1000 h under 0.3 mA cm−2. And the discharge capacity decay rate of the Li|LiFePO 4 battery after 600 cycles at 1 C is only 0.04% per cycle. The study will provide a promising electrolyte candidate for high energy all-solid-state lithium metal batteries. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur (Li‐S) batteries are in the spotlight because their outstanding theoretical specific energy is much higher than those of the commercial lithium ion (Li‐ion) batteries. Li‐S batteries are tough competitors for future‐developing energy storage in the fields of portable electronics and electric vehicles. However, the severe "shuttle effect" of the polysulfides and the serious damage of lithium dendrites are main factors blocking commercial production of Li‐S batteries. Owing to their superior nanostructure, electrospun nanofiber materials commonly show some unique characteristics that can simultaneously resolve these issues. So far, various novel cathodes, separators, and interlayers of electrospun nanofiber materials which are applied to resolve these challenges are researched. This review presents the fundamental research and technological development of multifarious electrospun nanofiber materials for Li‐S cells, including their processing methods, structures, morphology engineering, and electrochemical performance. Not only does the review article contain a summary of electrospun nanofiber materials in Li‐S batteries but also a proposal for designing electrospun nanofiber materials for Li‐S cells. These systematic discussions and proposed directions can enlighten thoughts and offer ways in the reasonable design of electrospun nanofiber materials for excellent Li‐S batteries in the near future. [ABSTRACT FROM AUTHOR]

Highlights • A novel hybrid Octaphenyl-POSS/PMIA membrane is successfully prepared. • The separator has outstanding thermal stability and strength. • The separator shows excellent ability to absorb and store liquid electrolyte. • The separator has high ionic conductivity and stable electrochemical window. • The battery presents high safety and excellent electrochemical performance. Abstract In this study, a hybrid Poly-m-phenyleneisophthalamide/Octaphenyl-Polyhedral oligomeric silsesquioxane (PMIA/Octaphenyl-POSS) membrane (HPPS) was fabricated by electrospinning technique and its application performance as lithium-ion battery separators was discussed. The organic-inorganic feature of Octaphenyl-POSS (OPS) endowed admirable compatibility of membrane matrix for the HPPS membranes. The nanofiber membranes with OPS nanoparticles were provided with commendable thermal stability, robust mechanical strength (21.79 MPa), high porosity and electrolyte uptake, which laid a good foundation for improving the safety and cycle performance of the cells with the separator. The lithium-ion battery with the HPPS separator displayed a high ionic conductivity of 1.93 × 10−3 S·cm−1 and a stable electrochemical window of 4.98 V. More significantly, the HPPS nanofiber membrane based Li/LiCoO 2 cell exhibited excellent cycling stability with high first discharge capacity up to 157.9 mAh·g−1 and superior capacity retention of 89.04% after 100 cycles. Therefore, the HPPS separator has extraordinary potential to be used in high-performance lithium-ion battery. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery is regarded as one of the promising next-generation energy storage to electrical and portable devices thanks to its extremely high theoretical capacity, energy density, good environmental protection and low cost. However, the practical application of lithium-sulfur battery is still greatly impeded by the low Coulombic efficiency and the short lifespan, which is mainly attributed to the polysulfide shuttle and the uncontrollable lithium dendrite growth. Suppressing the growth of the lithium dendrite and hindering the notorious reaction between soluble polysulfides and lithium are extremely critical not only to a safe and efficient lithium anode, but also to the high-capacity lithium-sulfur battery. A comprehensive review of various strategies for strengthening the anode stability of lithium-sulfur battery is presented in this paper, including modifying the electrolyte and current collector, employing artificial protection films and finding alternative anodes to replace the lithium anode. The effects of different selections and the resulting properties of the anodes on the overall lithium-sulfur battery performance are discussed. The current research challenges and future perspectives associated with lithium-sulfur battery anode are also discussed. [ABSTRACT FROM AUTHOR]

A novel tree-like cellulose nanofiber membrane was controllably fabricated via the electrospinning method by adding certain amount of tetra butyl ammonium chloride (TBAC) into the cellulose acetate solution followed by a deacetylation treatment process. The morphological structure, material structure and air filtration performance of both the cellulose and the cellulose acetate tree-like nanofiber membranes were characterized. Water contact angles, mechanical properties, and air filtration properties were also evaluated. The air filtration efficiency of cellulose acetate tree-like nanofiber membrane can reached 99.58%, and the eventually cellulose tree-like membrane still maintain 98.37%. The eventual cellulose tree-like nanofiber membranes exhibited small pore size, excellent hydrophilicity, good solvent resistance and preferable mechanical property. The small average pore size caused by the tree-like structure and the strong resistance to organic solvent can make it a potential candidate for the membrane separation. [ABSTRACT FROM AUTHOR]

In this study, F-doped tree-like nanofiber structural poly-m-phenyleneisophthalamide (PMIA) membranes are prepared via one-step electrospinning approach and their application performance as separators for lithium-sulfur batteries are discussed. The F-doped PMIA membrane can be regarded as matrix to form gel polymer electrolyte. The F doping endows the PMIA membranes with extraordinary high electrolyte uptake, excellent ability of preserving the liquid electrolyte and forceful chemisorption to polysulfides. And the tree-like structure effectively blocks polysulfides by the physical confinement. The lithium-sulfur cell with the F-doped PMIA separator exhibits high first-cycle discharge capacity of 1222.5 mAh g −1 and excellent cycling stability with good capacity retention of 745.7 mAh g −1 and coulombic efficiency of 97.97% after 800 cycles. The remarkable performance can be ascribed to the suppressed shuttle effects through both the physical trapping of polysulfides by the gel polymer electrolyte based on matrix with F-doped PMIA membrane and the tree-like structure in a working cell. [ABSTRACT FROM AUTHOR]

A smart tree-like nanofiber membrane with pH-responsivity was successfully fabricated by electrospinning poly(vinylidene fluoride)-graft-poly(acrylic acid) (PVDF-g-PAA). X-ray photoelectron spectroscopy, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and Brunauer-Emmett-Teller surface area measurement were employed to study the molecular structure and morphology of membranes. Through realizing protonation and deprotonation in response to the pH of the aqueous media, the as-prepared membrane is able to alter its wettability and conformation, resulting in the switchable surface oil/water wettability in the aqueous media. More importantly, the as-prepared membrane realized on-demand oil/water separation using gravity alone by switching the pH of the medium. Both separations exhibited excellent efficiency and flux which were attributed to the tree-like structure of the membrane. We believed that this smart membrane with such excellent controllable permeation has potential to be used for several applications, such as water purification, oil recovery and some separation systems. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery is considered as one of high performance batteries of the new generation owing to its extremely high theoretical capacity, energy density, good environmental protection and low cost. These features make it of great significance to serve as the next-generation battery especially in electric vehicles and portable devices. However, the practical application of lithium-sulfur battery is still hindered due to some obstacles including the low electrical and ionic conductivity of elemental sulfur, the discharge product Li 2 S and the “shuttle effect” caused by the dissolved polysulfide species. In this review, the current trends, fundamental studies and developments for lithium-sulfur battery separators including some modified functional and novel battery separators with the customized structure designs are presented and reviewed. The effects of different selections and the resulting properties of the separators affecting the overall lithium-sulfur battery performances are discussed as well. The current research directions and challenges associated with the use of battery separator and the future perspectives for this class of the battery separator are concluded as well. [ABSTRACT FROM AUTHOR]

In this study, the F-doped poly-m-phenyleneisophthalamide (PMIA) solution was synthesized by low temperature polymerization method and spun to be three-dimensional nanofibrous membranes by electrospinning. The Energy Dispersive X-Ray Spectroscopy and Fourier Transform Infrared Spectroscopy investigations verified that F was successfully doped in PMIA membrane. The X-ray diffraction patterns showed the crystallinity degree of PMIA membrane decreased with the addition of F. The morphology, pore size and aperture distribution tests manifested that the average diameter of F-PMIA fibers became finer and their distribution was more uniform than these of PMIA fibers. The electrolyte uptake, preserving liquid electrolyte, thermal stability and shrinkage resistance of the F-dopoed membrane were also significantly enhanced than that of pure PMIA membrane. The F-PMIA membrane could be acted as matrix to prepare gel polymer electrolyte. Finally, the F-doped PMIA membrane was used in the assembled coin cells to test the properties including the electronic conductivity, battery interfacial characteristics, electrochemical stability windows and cycle performances of battery. The lower electronic conductivity and interfacial resistance, higher electrochemical stability window (5.7 V) of F-doped PMIA membranes were obtained when comparing to the pure PMIA and commercial polyethylene membrane. The cell exhibited high first-cycle discharge capacity with 145 mAh g −1 and excellent cycling stability with good capacity retention of 93.1% and coulombic efficiency of 99.3% after 100 cycles. [ABSTRACT FROM AUTHOR]

The membranes for gel polymer electrolyte (GPE) for lithium-ion batteries were prepared by electrospinning a blend of poly(vinylidene fluoride) (PVdF) with cellulose acetate (CA). The performances of the prepared membranes and the resulted GPEs were investigated, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), porosity, hydrophilicity, electrolyte uptake, mechanical property, thermal stability, AC impedance measurements, linear sweep voltammetry, and charge-discharge cycle tests. The effect of the ratio of CA to PVdF on the performance of the prepared membranes was considered. It is found that the GPE based on the blended polymer with CA:PVdF =2:8 (in weight) has an outstanding combination property-strength (11.1 MPa), electrolyte uptake (768.2 %), thermal stability (no shrinkage under 80 °C without tension), and ionic conductivity (2.61 × 10 S cm). The Li/GPE/LiCoO battery using this GPE exhibits superior cyclic stability and storage performance at room temperature. Its specific capacity reaches up to 204.15 mAh g, with embedded lithium capacity utilization rate of 74.94 %, which is higher than the other lithium-ion batteries with the same cathode material LiCoO (about 50 %). [ABSTRACT FROM AUTHOR]

Lithium (Li) metal is deemed as a promising anode for next-generation high-energy-density battery. However, the rebellious dendrites growth leads to the low Coulombic efficiency and safety hazards, which has been a key challenge in the application of Li metal anode. Herein, the ZnF 2 /ZnS heterostructures and N-doped carbon decorated porous carbon nanofibers (ZnF 2 /ZnS/NC/PCNFs) are fabricated through the electro-blow spinning (EBS), metal-organic framework (MOF)-assisted method, and carbonization process. And its application performances as coating functional interlayer of lithium metal batteries (LMBs) to suppress the Li dendrites growth are systematically researched. The conductive interconnected skeleton of NC/PCNFs provides convenient electrons/ions transmission channels and reduces local current density. The lithiophilic ZnF 2 and ZnS nanoparticles can trigger similar alloying reaction with Li-ions to guide the uniform Li deposition. In particular, the inbuilt electric field triggered at the interface of ZnF 2 /ZnS heterostructures improves charge transfer and surface reaction kinetics. Combining with these merits, the Li|LiFePO 4 (Li|LFP) cells with ZnF 2 /ZnS/NC/PCNFs deliver an optimal initial discharge capacity of 143.2 mAh g−1 and capacity retention rate of 93.6% after 600 cycles at 1 C. Moreover, the Li|Li symmetric cells show lower overpotential than that without the interlayer. Extraordinarily, the lithium-sulfur (Li|S) cells with ZnF 2 /ZnS/NC/PCNFs also display excellent cycle stability due to the strong captured or adsorbed ability to dissolved lithium polysulfides. All these results reveal that the utilization of the ZnF 2 /ZnS/NC/PCNFs interlayer provides new insight for protecting the Li metal anode and improving the electrochemical properties and safety of LMBs. [Display omitted] • The ZnF 2 /ZnS/NC/PCNFs interlayer was successfully prepared. • The interlayer provided convenient ions/electrons transmission channel. • ZnF 2 /ZnS heterostructures could enhance the charge transfer kinetics. • The interlayer could inhibit the Li dendrites growth for LMBs and absorb lithium polysulfides for Li.|S batteries. [ABSTRACT FROM AUTHOR]

• A novel multifunctional interlayer is successfully prepared. • The prepared interlayer mainly contains N-doped porous carbon nanofibers and Mg-Al layered double hydroxides. • The interlayer can suppress the "shuttle effect" and accelerate the redox reaction kinetics. • The Li-S battery with the MALDH@NPCNFs interlayer shows stable long-term cycle performance. [Display omitted] Lithium-sulfur (Li-S) battery as a promising energy storage technology has attracted extensive concern. However, their practical performance is seriously limited by the dissolution and diffusion of long-chain polysulfides. In this study, a multifunctional cathodic interlayer was constructed, which composed by Mg-Al layered double hydroxides (MALDHs) modified N-doped honeycomb-like porous carbon nanofibers (NPCNFs). The NPCNFs in the prepared interlayer can combine the physical confinement of the porous structure and the chemical role of the nitrogen atoms to suppress the dissolved lithium polysulfide (LiPS). Furthermore, highly conductive interlayer contains NPCNFs can be regarded as a second current collector, and the hierarchical pores is beneficial to adapt the volume change during the redox process. More importantly, the obtained polar MALDHs not only can strongly interact with LiPS by chemical combination, but also enhance the redox kinetics by forming cooperative interface. As a result, the Li-S cells with the cathodic interlayers obtains a high initial discharge capacity of 1452 mAh g−1 at 0.2 C, superior rate capability up to 2 C rate with a capacity of 952 mAh g−1 and excellent long-term cycling stability by maintaining a low average capacity fading (0.065% per cycle) during 500 cycles at 1 C. Therefore, the interlayer contains MALDH@NPCNFs has extraordinary potential to be used in high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

Owing to high energy density, lithium sulfur (Li–S) battery is regarded as one of the most promising candidates for future energy storage. However, "shuttle effect" and sluggish redox kinetics of lithium polysulfides impede its practical application. Herein, a novel g-C 3 N 4 /Co-based MOFs derived chestnut-like superstructure (Co/CNT@DCNS) was prepared to act as the component of interlayer through a low-temperature one-step carbonization strategy. The prepared superstructure was constructed by the strong catalysis of 0D Co nanoparticles, high conductivity of 1D CNTs and excellent polysulfides adsorption of 2D defect C x N y nanosheets, which could not only ensure the rapid electrons/ions transport and fast redox kinetics, but also provide sufficient spaces for accommodating the volume expansion of active materials. Therefore, the cells with the prepared interlayer exhibited stable performances with an initial capacity of 1348.3 mAhg−1 and an extended cycling stability of 0.04% per cycle during the 1000 cycles at 1C. Even at a high sulfur loading of 3.1 mg cm−2, a specific capacity of 691.7 mAh g−1 can be maintained after 500 cycles at 0.5C. This work shares a convenient and safe strategy for the synthesis of multi-dimension, dual-functional and stable superstructure interlayer for advanced Li–S batteries. Image 1 [ABSTRACT FROM AUTHOR]

In this study, a novel MOFs-anchored-nanofiber framework (UiO-66-NH 2 @NFs) is designed via electrospinning. To hybridize with Nafion matrix, UiO-66-NH 2 @NFs/Nafion membranes with acid-base pairs are fabricated. In the framework, sulfonated poly(ether sulfone) (SPES) nanofibers with effective –SO 3 H groups serve as bonding platforms and UiO-66-NH 2 with –NH 2 groups act as co-reinforcement units tethering in nanofibers. As systematically studied and compared in membrane performance, the homogeneous UiO-66-NH 2 @NFs/Nafion membrane with a moderate UiO-66-NH 2 filler amount of 8 wt% present excellent performance on elevating proton conductivity of 0.27 S cm−1 (80 °C, 100% RH) and inhibiting methanol permeability of 7.54 × 10−7 cm2 s−1, respectively. The above superiorities can be attributed to the unique MOFs-anchored-nanofiber framework with balanced acid-base pairs. The interconnected UiO-66-NH 2 @NFs framework with hydrophilic SPES nanofibers and UiO-66-NH 2 offer consecutive proton transfer channels, making protons easily transfer via the hydration channels. Moreover, –NH 2 groups in UiO-66-NH 2 and –SO 3 H groups in matrix interact via acid-base pairs, which synergistically conducts protons via proton hopping channels in the membranes. Meanwhile, the good compatibility of UiO-66-NH 2 @NFs with Nafion matrix resulting from the tight electrostatically interactions between –NH 2 and –SO 3 H groups endow the hybrid membranes with suppressed methanol permeation and strengthened mechanical properties. Image 1 • UiO-66-NH 2 @NFs with acid-base pairs were built as proton-conducting highways. • Hybrid PEMs were prepared by incorporating UiO-66-NH 2 @NFs into Nafion matrix. • Acid-base interaction and consecutive proton conducting channels were well formed. • The hybrid PEMs exhibited high proton conductivity of 0.270 S cm−1 at 80 °C. [ABSTRACT FROM AUTHOR]