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Moisture-induced electric generation has emerged as a promising powering solution for next-generation wearable electronics since moisture is ubiquitous in the atmosphere. However, the practical applications of current film-shaped generators are limited by the challenge of wearable comfort and large-scale integration into wearables. Herein, we reported a strategy to prepare flexible and high-performance core-shell yarn-shaped moisture-induced electric generator (YMEG) via employing metal wire as the core electrode, polymer-salt solution-treated electrospun nanofiber mats as the active layer, and deposited sliver as the shell electrode. Through the moisture induced interaction between active layer and electrode, the obtained best performance of YMEG with length of 2 cm can produce a highly stable voltage of ∼0.8 V and a current density of 14.3 μA/cm2, reaching the state-of-the-art level among the reported one-dimensional fiber/yarn-shaped MEGs. Furthermore, benefiting from the weavability of YMEG, a dislocation ordered stacking strategy is created for effective integration of YMEG units into fabric, and realizing the simultaneous enhancement of output voltage and current. Such integrated fabric device can work normally under deformation and show successful practical use in power electronics and sensing system, demonstrating great potential to serve as an advanced energy accessory for wearable electronics. [Display omitted] • A novel flexible and high-performance core-shell yarn-shaped moisture-induced electric generator (MIEG) is developed via core-spun electrospinning technique followed with dip-drying treatment and sliver deposition. • The conjugated electrospinning technique is applied for yarn-shape MEG. • A dislocation-ordered stacking strategy is created for realizing the simultaneous enhancement of output voltage and current. • The integrated devices can work normally under deformation and shows successful practical use in power electronics and sensing humidity from humans. [ABSTRACT FROM AUTHOR]

Materials prepared on the base of bioactive silver compounds have become more and more popular. In the present work, the surface morphology, structure and properties, of electrospun Polylactide Polylactic acid (PLA) porous fibers containing various ratios of silver ions were investigated by a combination of X-ray photoelectron spectroscopy (XPS), universal testing machine, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and et al. The biological activities of the proposed porous fibers were discussed in view of the released silver ions concentration. Antibacterial properties of these porous fibers were studied using two bacterial strains: Escherichia coli ( E. coli ) and Methicillin-resistant Staphylococcus aureus (MRSA). Results of the antibacterial testing suggested that PLA porous fibers containing silver ions could be used as potent antibacterial wound dressing materials in the biomedical field. [ABSTRACT FROM AUTHOR]

Polylactide/polyethylene glycol/curcumin (PLA/PEG/Cur) composite nanofibers (CNFs) with varying ratios of PEG were successfully fabricated by electrospinning. Characterizations of the samples, such as the porous structure, crystalline structure, pore size, wetting property and Cur release property were investigated by a combination of scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and UV spectrophotometer. The antibacterial properties of the prepared porous CNFs against Escherichia coli bacteria were studied. The results showed that with the decrease of PEG in the CNFs, there appeared an evident porous structure on the CNF surface, and the porous structure could enhance the release properties of Cur from the CNFs. When the weight ratio (PEG:PLA) was 1:9, the pore structure of the nanofiber surface became most evident and the amount of Cur released was highest. However, the antibacterial effect of nonporous CNFs was better due to burst release over a short period of time. That meant that the porous structure of the CNFs could reduce the burst release and provide better control over the drug release. [ABSTRACT FROM AUTHOR]

Porous materials can be prepared by sol–gel method, hydrothermal synthesis method, electrospinning and other methods. In this paper, electrospun porous nanofibers were prepared by adjusting electrospinning parameters. And the properties of obtained porous nanofiber mats were investigated. Theoretical analysis and experiment research were carried out to research mechanical mechanism of electrospun porous nanofibers, and could be used to optimize and control the porous structure. The theoretical analysis results were further verified according to the experimental data. In addition, Bernoulli equation was used to study the electrospinning “splaying” process. We found the ratio of pore width to pore length was varied along with the variation of the internal pressure of the jet, and the internal pressure of the jet increases with the velocity of the charged jet decreases. [ABSTRACT FROM AUTHOR]