Biodegradable Poly (L-Lactic acid) Fibrous Membrane with Ribbon-Structured Fibers and Ultrafine Nanofibers Enhances Air Filtration Performance.

Here, the poly (l-lactic acid) (PLLA) membrane with multi-structured networks (MSN) is successfully prepared by electrospinning technology for the first time. It is composed of micron-sized ribbon-structured fibers and ultrafine nanofibers with a diameter of tens of nanometers, and they are connected to form the new network structure. Thanks to the special fiber morphology and structure, the interception and electrostatic adsorption ability for against atmospheric particulate matter (PM) are significantly enhanced, and the resistance to airflow is reduced due to the "slip effect" caused by ultrafine nanofibers. The PLLA MSN membrane shows excellent filtration performance with ultra-high filtration efficiency (>99.9% for PM2.5 and >99.5% for PM0.3) and ultra-low pressure drop (≈20 Pa). It has demonstrated filtration performance that even exceeds current non-biodegradable polymer materials, laying the foundation for future applications of biodegradable PLLA in the field of air filtration. In addition, this new structure also provides a new idea for optimizing the performance of other polymer materials.

Smart Bandage Based on a ZIF-8 Triboelectric Nanogenerator for In Situ Real-Time Monitoring of Drug Concentration.

For chronic wounds, frequent replacement of bandages not only increases the likelihood of secondary damage and the risk of cross infection but also wastes medication. Therefore, in situ real-time monitoring of the concentrations of residual drugs in bandages is crucial. Here, we propose a novel strategy that combines a triboelectric nanogenerator (TENG) with medical bandages to develop a smart bandage based on zeolite imidazolate framework TENG. During the process of wound healing, the electrical output of TENG changes with the continuous release of drugs. Based on the correlation between the electrical signal of TENG and drug concentration, the concentration of residual drugs in the bandage can be monitored in real-time in situ, guiding medical staff to replace the bandage at the most appropriate time. The smart bandage based on TENG provides a new strategy for in situ real-time monitoring of drug concentration and also provides an ideal and feasible solution for the field of biomedical drug sensing.

Unlocking Efficient Hydrogen Production: Nucleophilic Oxidation Reactions Coupled with Water Splitting.

Electrocatalytic water splitting driven by sustainable energy is a clean and promising water-chemical fuel conversion technology for the production of high-purity green hydrogen. However, the sluggish kinetics of anodic oxygen evolution reaction (OER) pose challenges for large-scale hydrogen production, limiting its efficiency and safety. Recently, the anodic OER has been replaced by a nucleophilic oxidation reaction (NOR) with biomass as the substrate and coupled with a hydrogen evolution reaction (HER), which has attracted great interest. Anode NOR offers faster kinetics, generates high-value products, and reduces energy consumption. By coupling NOR with hydrogen evolution reaction, hydrogen production efficiency can be enhanced while yielding high-value oxidation products or degrading pollutants. Therefore, NOR-coupled HER hydrogen production is another new green electrolytic hydrogen production strategy after electrolytic water hydrogen production, which is of great significance for realizing sustainable energy development and global decarbonization. This review explores the potential of nucleophilic oxidation reactions as an alternative to OER and delves into NOR mechanisms, guiding future research in NOR-coupled hydrogen production. It assesses different NOR-coupled production methods, analyzing reaction pathways and catalyst effects. Furthermore, it evaluates the role of electrolyzers in industrialized NOR-coupled hydrogen production and discusses future prospects and challenges. This comprehensive review aims to advance efficient and economical large-scale hydrogen production.

Amorphous Fe2O3 Anchored on N-Doped Graphene with Internal Micro-Channels as an Active and Durable Anode for Sodium-Ion Batteries.

The reduced graphene oxide (rGO) exhibits outstanding electrical conductivity and a high specific surface area, making it a promising material for various applications. Fe2O3 is highly desirable due to its significant theoretical capacity and cost-effectiveness, high abundance, and environmental friendliness. However, the performance of these r-GO/Fe2O3 composite electrodes still needs to be further improved, especially in terms of cycle stability. The composite of Fe2O3 anchored on N-doped graphene with inside micro-channels (Fe2O3@N-GIMC) was used to be efficiently prepared. Because the inside channels can furnish extra transmission pathways and absorption websites and the interconnected structure can efficaciously forestall pulverization and aggregation of electrode materials. In addition, N doping is also beneficial to improve its electrochemical performance. Thus, it demonstrates exceptional sodium storage characteristics, including notable electrochemical activity, impressive initial Coulombic efficiency, and favorable rate performance. The optimized Fe2O3@N-GIMC indicates outstanding discharge capacity (573.5 mAh g-1 at 1 A g-1), significant rate performance (333.6 mAh g-1 at 8 A g-1), and stable long-term cycle durability (308.9 mAh g-1 after 1000 cycles at 1 A g-1, 200.8 mAh g-1 after 4000 cycles at 1 A g-1) as a sodium-ion battery anode. This presents a new approach for preparing graphene-based high-functional composites and lays a stable basis for further expanding its application field.

Dendritic boron and nitrogen doped high-entropy alloy porous carbon fibers for high-efficiency hydrogen evolution reaction.

Among various electrocatalysts, high-entropy alloys (HEAs) have gained significant attention for their unique properties and excellent catalytic activity in the hydrogen evolution reaction (HER). However, the precise synthesis of HEA catalysts in small sizes remains challenging, which limits further improvement in their catalytic performance. In this study, boron- and nitrogen-doped HEA porous carbon nanofibers (HE-BN/PCNF) with an in situ-grown dendritic structure were successfully prepared, inspired by the germination and growth of tree branches. Furthermore, the dendritic fibers constrained the growth of HEA particles, leading to the synthesis of quantum dot-sized (1.67 nm) HEA particles, which also provide a pathway for designing HEA quantum dots in the future. This work provides design ideas and guiding suggestions for the preparation of borated HEA fibers with different elemental combinations and for the application of dendritic nanofibers in various fields.

Rationally designing of Co-WS2 catalysts with optimized electronic structure to enhance hydrogen evolution reaction.

Designing and developing cost-effective, high-performance catalysts for hydrogen evolution reaction (HER) is crucial for advancing hydrogen production technology. Tungsten-based sulfides (WSx) exhibit great potential as efficient HER catalysts, however, the activity is limited by the larger energy required for water dissociation under alkaline conditions. Herein, we adopt a top-down strategy to construct heterostructure Co-WS2 nanofiber catalysts. The experimental results and theoretical simulations unveil that the work functions-induced built-in electric field at the interface of Co-WS2 catalysts facilitates the electron transfer from Co to WS2, significantly reducing water dissociation energy and optimizing the Gibbs free energy of the entire reaction step for HER. Besides, the self-supported catalysts of Co-WS2 nanoparticles confining 1D nanofibers exhibit an increased number of active sites. As expected, the heterostructure Co-WS2 catalysts exhibit remarkable HER activity with an overpotential of 113 mV to reach 10 mA cm-2 and stability with 30 h catalyzing at 23 mA cm-2. This work can provide an avenue for designing highly efficient catalysts applicable to the field of energy storage and conversion.

Regulating Hydrogen/Oxygen Species Adsorption via Built-in Electric Field -Driven Electron Transfer Behavior at the Heterointerface for Efficient Water Splitting.

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high-efficiency AWE. Herein, WC1-x/Mo2C nanoparticle-embedded carbon nanofiber (WC1-x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1-x, the electrocatalysts of WC1-x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1-x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm-2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d-band center for WC1-x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built-in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields.

Preparation and Peculiar Magnetic Properties at Low Temperatures of La1.85Sr0.15CuO4 Nanofibers.

Herein, the preparation process, morphology, structure, and magnetic properties of La1.85Sr0.15CuO4 (LSCO) cobweb-like nanofibers are reported. LSCO nanofibers with a regular grain size distribution are successfully prepared via electrospinning, followed by calcination. We conducted morphology analysis and elemental distribution using electron microscopy and energy-dispersive X-ray spectroscopy (EDS), respectively. Additionally, magnetic property testing was performed using a vibrating sample magnetometer (VSM) to confirm the superconducting properties of the samples. Interestingly, our samples exhibited a superconducting transition temperature, Tc, of 25.21 K, which showed some disparity compared to similar works. Furthermore, we observed a ferromagnetic response at low temperatures in the superconducting nanofibers. We attribute these phenomena to the effects generated by surface states of nanoscale superconducting materials.

Oxygen Vacancy-Enhanced Centrosymmetric Breaking of SrFeO3- x for Piezoelectric-Catalyzed Synthesis of H2O2.

Normally, only noncentrosymmetric structure of the materials can potentially be piezoelectric. Thus, it is limited in the field of piezoelectricity for the centrosymmetric structure of the material. In this work, the performance of piezoelectricity is successfully achieved from centrosymmetric SrFeO3- x by modulating oxygen vacancies, which have a surface piezoelectric potential up to 93 mV by using Kelvin-probe force microscopy (KPFM). Moreover, the piezoelectric effects of SrFeO3- x are also evaluated by piezoelectric catalytic effect and density functional theory calculations (DFT). The results show that the piezo-catalytic degradation of tetracycline reaches 96% after 75 min by ultrasonic mechanical vibration and the production of H2O2 by SrFeO3- x piezoelectric synthesis could reach 1821 µmol L-1. In addition, the DFT results indicate that the intrinsic effect of oxygen vacancies effectively promotes the adsorption and activation of O2 and H2O as well as intermediates and improves the piezoelectric catalytic activity. This work provides an effective basis for realizing the piezoelectricity of centrosymmetric materials and regulating the development of piezoelectric catalytic properties.

In-situ electrospinning with precise deposition of antioxidant nanofiber facial mask loaded with Enteromorpha prolifera polysaccharides.

In order to fabricate a novel antioxidant nanofiber facial mask, a metal cone modified in-situ electrospinning with precise deposition was employed by utilizing Enteromorpha prolifera polysaccharides (EPPs). The metal cone could control the deposition area to achieve precise fabrication of facial mask on skin. The EPPs exhibited remarkable antioxidant ability, as evidenced by the half-maximal inhibitory concentrations (IC50) of 1.44 mg/mL and 0.74 mg/mL against DPPH and HO• free radicals, respectively. The antioxidant ability of the facial mask was improved by elevating the electrospinning voltage from 15 kV to 19 kV, due to the improved release capacity of EPPs by 7.09 %. Moreover, the facial mask demonstrated robust skin adhesion and moisture-retaining properties compared with commercial facial mask, which was benefited by the in-situ electrospinning technology. Furthermore, cytotoxicity assay, animal skin irritation test, and ocular irritation test collectively affirmed the safety of the facial mask. Thus, this research introduces a novel in situ electrospinning with precise deposition method and a natural antioxidant additive for preparing facial mask.

Electrospun Cellulose Nanocrystals Reinforced Flexible Sensing Paper for Triboelectric Energy Harvesting and Dynamic Self-Powered Tactile Perception.

The technical synergy between flexible sensing paper and triboelectric nanogenerator (TENG) in the next stage of artificial intelligence Internet of Things engineering makes the development of intelligent sensing paper with triboelectric function very attractive. Therefore, it is extremely urgent to explore functional papers that are more suitable for triboelectric sensing. Here, a cellulose nanocrystals (CNCs) reinforced PVDF hybrid paper (CPHP) is developed by electrospinning technology. Benefitting from the unique effects of CNCs, CPHP forms a solid cross-linked network among fibers and obtains a high-strength (25 MPa) paper-like state and high surface roughness. Meanwhile, CNCs also improve the triboelectrification effect of CPHP by assisting the PVDF matrix to form more electroactive phases (96% share) and a higher relative permittivity (17.9). The CPHP-based TENG with single electrode configuration demonstrates good output performance (open-circuit voltage of 116 V, short-circuit current of 2.2 µA and power density of 91 mW m-2 ) and ultrahigh pressure-sensitivity response (3.95 mV Pa-1 ), which endows CPHP with reliable power supply and sensing capability. More importantly, the CPHP-based flexible self-powered tactile sensor with TENG array exhibits multifunctional applications in imitation Morse code compilation, tactile track recognition, and game character control, showing great prospects in the intelligent inductive device and human-machine interaction.

On-Site Construction of a Full-Thickness Skin Equivalent with Endothelial Tube Networks via Multilayer Electrospinning for Wound Coverage.

Novel full-thickness skin substitutes are of increasing interest due to the inherent limitations of current models lacking capillary networks. Herein, we developed a novel full-thickness skin tissue containing blood capillary networks through a layer-by-layer assembly approach using a handy electrospinning apparatus and evaluated its skin wound coverage potential in vivo. The average diameter and thickness of fabricated poly-ε-caprolactone-cellulose acetate scaffolds were easily tuned in the range of 474 ± 77-758 ± 113 nm and 9.43 ± 2.23-29.96 ± 5.78 µm by varying electrospinning distance and duration, as indicated by FE-SEM. Besides, keratinocytes exhibited homogeneous differentiation throughout the fibrous matrix prepared with electrospinning distance and duration of 9 cm and 1.5 min within five-layer (5L) epidermal tissues with thickness of 135-150 µm. Moreover, coculture of vascular endothelial cells, circulating fibrocytes, and fibroblasts within the 5L dermis displayed network formation in vitro, resulting in reduced inflammatory factor levels and enhanced integration with the host vasculature in vivo. Additionally, the skin equivalent grafts consisting of the epidermal layer, biomimetic basement membrane, and vascularized dermis layer with an elastic modulus of approximately 11.82 MPa exhibited accelerated wound closure effect indicative of re-epithelialization and neovascularization with long-term cell survival into the host, which was confirmed by wound-healing rate, bioluminescence imaging activity, and histological analysis. It is the first report of a full-thickness skin equivalent constructed using a battery-operated electrospinning apparatus, highlighting its tremendous potential in regenerative medicine.

Constructing CoO/Mo2 C Heterostructures with Interfacial Electron Redistribution Induced by Work Functions for Boosting Overall Water Splitting.

Space charge transfer of heterostructures driven by the work-function-induced built-in field can regulate the electronic structure of catalysts and boost the catalytic activity. Herein, an epitaxial heterojunction catalyst of CoO/Mo2 C with interfacial electron redistribution induced by work functions (WFs) is constructed for overall water splitting via a novel top-down strategy. Theoretical simulations and experimental results unveil that the WFs-induced built-in field facilitates the electron transfer from CoO to Mo2 C through the formed "Co─C─Mo" bond at the interface of CoO/Mo2 C, achieving interfacial electron redistribution, further optimizing the Gibbs free energy of primitive reaction step and then accelerating kinetics of hydrogen evolution reaction (HER). As expected, the CoO/Mo2 C with interfacial effects exhibits excellent HER catalytic activity with only needing the overpotential of 107 mV to achieve 10 mA cm-2 and stability for a 60-h continuous catalyzing. Besides, the assembled CoO/Mo2 C behaves the outstanding performance toward overall water splitting (1.58 V for 10 mA cm-2 ). This work provides a novel possibility of designing materials based on interfacial effects arising from the built-in field for application in other fields.

Long-term aged fibrous polypropylene microplastics promotes nitrous oxide, carbon dioxide, and methane emissions from a coastal wetland soil.

Microplastics (MPs) has been suggested that it can greatly affect soil greenhouse gases (GHGs) emissions via altering soil physical, chemical, and biological properties. However, the difference in GHGs emissions, especially for those from coastal wetland soils, between varied aged MPs was rarely explored and the underlying mechanisms of GHGs emissions affected by the aged MPs were poorly understood. Therefore, the implications of fibrous polypropylene MPs (FPP-MPs) exposure on N2O, CO2, and CH4 emissions were examined by a 60-day soil incubation experiment. Compared with the control, the additions of un-aged FPP-MPs with both two rates (0.2 and 2 %) and aged FPP-MPs with a low rate (0.2 %) showed an insignificant effect on N2O emission, while the aged FPP-MPs added with a high rate (2 %) resulted in a remarkably increase in N2O emission, especially for those of the 30-day-aged FPP-MPs. A significant increase in CO2 emission was only observed in the 30-day-aged FPP-MPs treatments, compared with the control, and a higher addition rate produced a higher increase of CO2 emission. Regarding CH4 emission, it was significantly increased by adding aged FPP-MPs, and a longer aging period or/and a higher addition rate generated a higher degree of promotion of CH4 emission. However, compared with the CO2 emission, the quantity of CH4 emission was extremely low. These increased GHGs emissions can be ascribed to the improvements in soil physical structure and other chemical properties (e.g., pH and contents of soil organic matter and dissolved organic carbon) and enhancements in the abundances of denitrification- and carbon mineralization-related microorganisms. Overall, our results highlight the risk of elevated GHGs emissions from the soil polluted with 30-day-aged FPP-MPs, which should not be ignored as long-term aged FPP-MPs continue to increase in coastal wetland soils.

MXene@Hydrogel composite nanofibers with the photo-stimulus response and optical monitoring functions for on-demand drug release.

The photo-stimulus response has the advantage of non-invasiveness, which could be used to control the "on" and "off" of drug release achieving on-demand release. Herein, we design a heating electrospray during electrospinning to prepare photo-stimulus response composite nanofibers consisting of MXene@Hydrogel. This heating electrospray enables to spray MXene@Hydrogel during the electrospinning process, and the hydrogel is uniformly distributed which cannot be achieved by the traditional soaking method. In addition, this heating electrospray can also overcome the difficulty that hydrogels are hard to be uniformly distributed in the inner fiber membrane.The "on" and "off" state of drug release could be controlled by light. Not only near infrared (NIR) light but also sunlight could trigger the drug release, which could benefit outdoor use when cannot find NIR light. Evidence by hydrogen bond has been formed between MXene and Hydrogel, the mechanical property of MXene@Hydrogel composite nanofibers is significantly enhanced, which is conducive to the application of human joints and other parts that need to move. These nanofibers also possess fluorescence property, which is further used to real-time monitor the in-vivo drug release. No matter the fast or slow release, this nanofiber can achieve sensitive detection, which is superior to the current absorbance spectrum method.

Enhanced Visible-Photocatalytic Activities in Strong Acids and Strong Alkalis of Flexible Iron-SrTiO3 Nanofibrous Membranes.

Traditional SrTiO3 (STO) materials have high brittleness and poor deformation resistance. In this work, macroscopically flexible iron-doped SrTiO3 (SFTO) nanofibrous membranes were prepared by electrospinning and calcination, which can be easily isolated and can maintain integrity to recycle as photocatalysts. Moreover, the SFTO nanofibrous membranes showed enhanced photocatalytic performance under strong acids (pH = 2) and strong alkalis (pH = 12). The SFTO nanofibrous membranes increased the catalytic rate of Congo red (CR) dye by about 10 times in visible light. The mechanism of photocatalytic activity enhancement was discussed by the combined effects of hydroxyl radicals and superoxide radicals. The successful preparation of SFTO nanofibrous membranes has offered a simple and economical approach to photocatalysis as well as environmental remediation.

Acid and alkali-resistant fabric-based triboelectric nanogenerator for self-powered intelligent monitoring of protective clothing in highly corrosive environments.

The corrosion of materials severely limits the application scenarios of triboelectric nanogenerators (TENGs), especially in laboratories, chemical plants and other fields where leakage of chemically corrosive solutions is common. Here, we demonstrate a chemical-resistant triboelectric nanogenerator (CR-TENG) based on polysulfonamide (PSA) and polytetrafluoroethylene (PTFE) non-woven fabrics. The CR-TENG can stably harvest biological motion energy and perform intelligent safety protection monitoring in a strong corrosive environment. After treatment with strong acid and alkali solution for 7 days, the fabric morphology, diameter, tensile properties and output of CR-TENG are not affected, showing high reliability. CR-TENG integrated into protective equipment can detect the working status of protective equipment in real time, monitor whether it is damaged, and provide protection for wearers working in high-risk situations. In addition, the nonwoven-based CR-TENG has better wearing comfort and is promising for self-powered sensing in harsh environments.

Synergistic Effects of Magnetic Z-Scheme g-C3N4/CoFe2O4 Nanofibres with Controllable Morphology on Photocatalytic Activity.

The rational design of interfacial contacts plays a decisive role in improving interfacial carrier transfer and separation in heterojunction photocatalysts. In Z-scheme photocatalysts, the recombination of photogenerated electron-hole pairs is prevented so that the redox capacity is maintained. Here, one-dimensional graphitic carbon nitride (g-C3N4)/CoFe2O4 fibres were synthesised as a new type of magnetic Z-scheme visible-light photocatalyst. Compared with pure g-C3N4 and CoFe2O4, the prepared composite photocatalysts showed considerably improved performance for the photooxidative degradation of tetracycline and methylene blue. In particular, the photodegradation efficiency of the g-C3N4/CoFe2O4 fibres for methylene blue was approximately two and seven times those of g-C3N4 and CoFe2O4, respectively. The formation mechanism of the Z-scheme heterojunctions in the g-C3N4/CoFe2O4 fibres was investigated using photocurrent spectroscopy and electrochemical impedance spectroscopy. We proposed that one of the reasons for the improved photodegradation performance is that the charge transport path in one-dimensional materials enables efficient photoelectron and hole transfer. Furthermore, the internal electric field of the prepared Z-scheme photocatalyst enhanced visible-light absorption, which provided a barrier for photoelectron-hole pair recombination.

Superhydrophobic aerogel blanket with magnetic and solar heating effect enables efficient continuous cleanup of highly viscous crude oil.

Rapid cleanup of highly-viscous oil spills the sea is eagerly desired while still remains a great challenge. Hydrophobic and lipophilic adsorbents are regarded as ideal candidate for oil spill remediation. However, traditional adsorbents are not suitable for viscous crude oil, which would block the porous structure and lead to poor adsorption efficiency. In this work, a non-contact responsive superhydrophobic SiO2 aerogel blankets (SAB) with excellent magnetic and solar heating effect for efficient removal of viscosity oils under harsh environments was developed, via assembled MXene and Fe3O4/polydimethylsiloxane layer-by-layer along the SAB skeleton (Fe3O4/MXene@SAB). The Fe3O4/MXene@SAB exhibited excellent compression tolerance (compression stress 70.69 kPa), superhydrophobic performance (water contact angle 166°), and corrosion resistance (weak acid/strong base). Due to high water repellency and stable porous structure, the Fe3O4/MXene@SAB could successfully separate oil-water mixture, while with remarkable separation flux (1.50-3.19 × 104 L m-2 h-1), and separation efficiency (99.91-99.98 %). Furthermore, the responsive Fe3O4/MXene@SAB also showed outstanding magnetic-heating and solar-heating conversion efficiency, which could continuously separate high viscosity crude oil from seawater by pump even under relatively low magnetic fields and mild sun. The superhydrophobic blankets hold great promise for efficient treatment of heavy oil spills.

Stretchable, flexible and breathable polylactic acid/polyvinyl pyrrolidone bandage based on Kirigami for wounds monitoring and treatment.

Chronic wounds are slow to recover. During treatment, the dressing needs to be removed to check the recovery status, a process that often results in wound tears. Traditional dressings lack stretching and flexing properties and are not suitable using on wounds in joints, which require movement from time to time. In this study, we present a stretchable, flexible and breathable bandage consisting of three layers, including Mxene coating on the top, the polylactic acid/polyvinyl pyrrolidone (PLA/PVP) layer designed as Kirigami in the middle, and the f-sensor at the bottom. By the way, the f-sensor is in contact with the wound sensing real-time microenvironmental changes due to infection. When the infection intensifies, the Mxene coating at the top is utilized to enable anti-infection treatment. And Kirigami structure of PLA/PVP ensures that this bandage has stretchability, bendability, and breathability. The stretch of the smart bandage increases to 831 % compared to the original structure, and the modulus reduces to 0.04 %, which adapts extremely well to the movement of the joints and relieves the pressure on the wound. This monitoring-treatment closed-loop working mode, eliminating the need to remove dressings and avoid tissue tearing, shows a promising capability in the field of surgical wound care.