In the electrospinning process, a modified parallel electrode method (MPEM), conducted by placing a positively charged ring between the needle and the parallel electrode collector, was used to fabricate highly aligned carbon nanotubes/polyacrylonitrile (CNTs/PAN) composite nanofibers. Characterizations of the samples—such as morphology, the degree of alignment, and mechanical and conductive properties—were investigated by a combination of scanning electron microscopy (SEM), transmission electron microscopy (TEM), universal testing machine, high-resistance meter, and other methods. The results showed the MPEM could improve the alignment and uniformity of electrospun CNTs/PAN composite nanofibers, and enhance their mechanical and conductive properties. This meant the successful preparation of highly aligned CNT-reinforced PAN nanofibers with enhanced physical properties, suggesting their potential application in appliances and communication areas.

Developing highly active, stable, and cost-effective cathode oxygen reduction reaction (ORR) catalysts is of great practical significance to promote the widespread applicability of fuel cells (FCs). Recent studies have witnessed remarkable progress in exploring the synthesis of high-performance ORR catalysts. Platinum group metal (PGM)-free catalysts with metal–nitrogen–carbon (M–N–C) sites are considered to be promising candidates for ORR catalysts due to their low cost and good applicability to multiple ORR steps. Here, we provide a focused discussion on the design strategies of high-efficiency M–N–C catalyst synthesis from the aspects of increasing active site density, improving intrinsic activity, facilitating mass transfer and avoiding the linear scaling relationship (LSR). The synthesis of M–N–C single-atom catalysts opens up a new way to increase active site density. The selection of an appropriate central metal and coordination atom as well as the adjustment of the local coordination environment are very crucial to enhance catalyst intrinsic activity. The reasonable design of a porous structure is an important prerequisite to promote mass transfer and build the largest three-phase interface. The development of new active sites makes it possible to avoid the LSR and prepare catalysts with ultra-low overpotential. Furthermore, the main mechanisms causing the rapid degradation of M–N–C catalyst activity, such as active site demetallization, H₂O₂ hazards and flooding problems, are discussed, and effective mitigation strategies are proposed to improve the M–N–C catalyst stability. Ultimately, the designs of high performance M–N–C catalysts for the ORR are summarized and prospected.

The current physical health care system has gradually evolved into a form of virtual hospitals communicating with sensors, which can not only save time but can also diagnose a patient’s physical condition in real time. Textile-based wearable sensors have recently been identified as detection platforms with high potential. They are developed for the real-time noninvasive detection of human physiological information to comprehensively analyze the health status of the human body. Sweat comprises various chemical compositions, which can be used as biomarkers to reflect the relevant information of the human physiology, thus providing references for health conditions. Combined together, textile-based sweat sensors are more flexible and comfortable than other conventional sensors, making them easily integrated into the wearable field. In this short review, the research progress of textile-based flexible sweat sensors was reviewed. Three mechanisms commonly used for textile-based sweat sensors were firstly contrasted with an introduction to their materials and preparation processes. The components of textile-based sweat sensors, which mainly consist of a sweat transportation channel and collector, a signal-selection unit, sensing elements and sensor integration and communication technologies, were reviewed. The applications of textile-based sweat sensors with different mechanisms were also presented. Finally, the existing problems and challenges of sweat sensors were summarized, which may contribute to promote their further development.

Electrospun nanofiber membranes (NFMs) have high porosity and a large specific surface area, which provide a suitable environment for the complex and dynamic wound healing process and a large number of sites for carrying wound healing factors. Further, the design of the nanofiber structure can imitate the structure of the human dermis, similar to the natural extracellular matrix, which better promotes the hemostasis, anti-inflammatory and healing of wounds. Therefore, it has been widely studied in the field of wound dressing. This review article overviews the development of electrospinning technology and the application of electrospun nanofibers in wound dressings. It begins with an introduction to the history, working principles, and transformation of electrospinning, with a focus on the selection of electrospun nanofiber materials, incorporation of functional therapeutic factors, and structural design of nanofibers and nanofiber membranes. Moreover, the wide application of electrospun NFMs containing therapeutic factors in wound healing is classified based on their special functions, such as hemostasis, antibacterial and cell proliferation promotion. This article also highlights the structural design of electrospun nanofibers in wound dressing, including porous structures, bead structures, core-shell structures, ordered structures, and multilayer nanofiber membrane structures. Finally, their advantages and limitations are discussed, and the challenges faced in their application for wound dressings are analyzed to promote further research in this field.