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Hydrogen is regarded as an ideal energy carrier to cope with the energy crisis and environmental problems due to its high energy density, cleanliness, and renewability. Although there are several primary methods of industrial hydrogen production, hydrogen evolution reaction (HER) is an efficient, eco-friendly, and sustainably green method for the preparation of hydrogen which has attracted considerable attention. However, this technique is characterized by slow reaction kinetics and high energy potential owing to lack of electrocatalysts with cost-effective and high performance which impedes its scale-up. To address this issue, various studies have focused on electrospun micro/nanofiber-based electrocatalysts for HER due to their excellent electron and mass transport, high specific surface area, as well as high porosity and flexibility. To further advance their development, recent progress of highly efficient HER electrospun electrocatalysts is reviewed. Initially, the characteristics of potential high-performance electrocatalysts for HER are elucidated. Subsequently, the advantages of utilizing electrospinning technology for the preparation of electrocatalysts are summarized. Then, the classification of electrospun micro/nanofiber-based electrocatalysts for HER are analyzed, including metal-based electrospun electrocatalyst (noble metals and alloys, transition metals, and alloys), metal–non-metal electrocatalysts (metal sulfide-based electrocatalysts, metal oxide-based electrocatalysts, metal phosphide-based electrocatalysts, metal nitride-based electrocatalysts, and metal carbide-based electrocatalysts), metal-free electrospun micro/nanofiber-based electrocatalysts, and hybrid electrospun micro/nanofiber-based electrocatalysts. Following this, enhancement strategies for electrospun micro/nanofiber-based electrocatalysts are discussed. Finally, current challenges and the future research directions of electrospun micro/nanofiber-based electrocatalysts for HER are concluded. [ABSTRACT FROM AUTHOR]

The rapid development and popularization of smart and portable electronic devices have led to increasingly related electromagnetic pollution affecting human health and equipment safety. Thus, designing high‐performance electromagnetic interference (EMI) shielding materials with lightweight, flexible, and easy preparation is urgent. The intrinsic physiochemical properties of electrospun micro/nanofibers provide an attractive potential to ease and accelerate the next‐generation EMI shielding materials. Here, a detailed review of the electrospun EMI shielding materials is established. First, this article outlines the shielding mechanism of EMI shielding materials obtained via electrospinning. Then, the affecting factors of electrospinning process conditions on the resulting EMI shielding micro/nanofibers are discussed. Next, diverse fillers that contribute to the EMI shielding efficiency of electrospun materials are demonstrated. Finally, the conclusion and prospects are introduced, hopefully contributing to assisting with more comprehensive and rational designs of high‐performance electrospun fiber‐based EMI shielding for various applications. Priority measures and future directions are suggested for the future development of electrospun EMI shielding materials. [ABSTRACT FROM AUTHOR]

Biosensors are analytical tools that can be used as simple, real-time and effective devices in clinical diagnosis, food analysis, and environmental monitoring. In the last years, electrospun nanofiber's engineering has emerged as a possible strategy to improve the performance of biosensor devices. These nanostructures present a high surface-to-volume ratio, interconnected porous structure, low barrier to diffusion, and adjustable surface functionality. Additionally, nanofibers have also been demonstrated to work efficiently as platforms to immobilize biomolecules, providing a suitable microenvironment to biologically active molecules, which is beneficial for biosensing performance. This review aims to highlight the different strategies (e.g., adsorption, covalent binding, entrapment, and imprinting) for immobilizing functional receptors onto nanofibers surface for the development of specific and sensitive (bio)chemical assays, which can be used for a wide range of applications. The attractive features of electrospun nanofibers and the biorecognition elements properties are also presented and discussed. Finally, the current challenges and future opportunities for the design of nanofiber-based biosensing interfaces are also addressed.

BACKGROUND Mosquitoes are hematophagous insects of major public health concern, serving as vectors of many diseases. Available products for personal protection against mosquitoes lack adequate efficacy and in most cases need to be reapplied or replaced frequently. In recent years, the encapsulation of the active repellents in various matrices has arisen as an alternative method for the development of new‐generation repellent systems. The aim of the present study was to explore the potential of functional micro/nanofibrous matrices as systems for the sustained release of the highly volatile insect‐repellent citronella oil. RESULTS: Micro/nanofibrous single‐ and triple‐layer systems incorporating citronella oil as the active agent were developed via the electrospinning technique using the low‐cost, non‐toxic, biodegradable polymers cellulose acetate and polyvinylpyrrolidone. All the micro/nanofiber systems produced exhibited prolonged release of citronella oil and a high repellent activity in laboratory bioassays against the mosquito Aedes albopictus for at least 4 weeks. CONCLUSION: Considering the high volatility of the embedded repellent, the present study demonstrates the strong potential of the micro/nanofibrous matrices to act as carriers of highly volatile repellents for an effective and sustained protection from mosquitoes. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

New systems for the controlled release of 1,7-dioxaspiro[5.5]undecane and ( Z)-7-tetradecenal, the sex pheromones of olive fruit fly, Bactrocera oleae, and olive moth, Prays oleae, respectively, were developed utilizing electrospun micro/nanofiber matrices from inexpensive, biodegradable polymers, namely polycaprolactone, cellulose acetate and polyhydroxybutyrate. The incorporation of the pheromones in 5, 10 and 20% w/w in the electrospinning polymer blends allowed for the production of fiber mats with variable loading levels and release rates, ensuring however in all cases the release of pheromones for more than 16 weeks. Laboratory bioassays and field trapping tests showed that the fiber mats obtained from electrospinning of polyhydroxybutyrate solution containing 5% w/w 1,7-dioxaspiro[5.5]undecane and polycaprolactone solution containing 5% w/w ( Z)-7-tetradecenal were almost twice as effective in attracting B. oleae and P. oleae males, respectively, in comparison to the positive controls used. [ABSTRACT FROM AUTHOR]

Polyvinylpyrrolidone(PVP) used as a complexant, is reacted with zinc acetate (Zn(CH3COO)2 ) and cobaltous acetate (Co(CH3COO)2 ) to prepare precursor solution. Co-doped ZnO micro/nanofibers can be prepared after calcinating the PVP/Zn (CH3COO)2/Co(CH3COO)2 electrospun nanofibers. The obtained fiber is characterized by differential thermal gravimetric analysis(TG), XRD diffraction analysis (XRD) and scanning electron microscopy(SEM). The photocatalytic activityof nanofibers toward the decomposition of methyl orange was investigated. The results show that Co-doped ZnO micro/nanofibers has an excellent photocatalytic activity of methyl orange, with a degeneration rate of 93% at 80min. [ABSTRACT FROM AUTHOR]