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Herein, a hydrogen‐bonded cobalt porphyrin framework is presented that can efficiently host iodine and serve as an electrocatalyst for aqueous zinc‐iodine (Zn‐I2) organic batteries. The Fourier Transform infrared spectroscopy (FT‐IR), X‐ray Photoelectron Spectroscopy (XPS), and Density functional theory (DFT) results demonstrate that hydrogen‐bonded organic frameworks (HOFs) possess excellent adsorption properties for iodine species. In situ Raman spectroscopy illustrates that the redox mechanism of Zn‐I2 battery depends on the redox reaction of I/I−, with I3−/I5− serving as intermediary products. The in situ Ultraviolet‐visible (UV–vis) spectroscopy further reveals that HOFs restrict polyiodide solubilization. The aqueous Zn‐I2 organic batteries with I2@PFC‐72‐Co cathodes exhibit excellent rate capability, achieving 134.9 mAh g−1 at 20 C. Additionally, these batteries demonstrate long‐term cycle stability, enduring > 5000 cycles at 20 C. The impressive electrochemical performance of I2@PFC‐72‐Co can be attributed to the cooperative Co single‐atom (CoSA) electrocatalyst in the HOF‐Co structure. Moreover, the benzene ring structure and the carboxyl functional group of HOFs possess a strong ability to adsorb iodine and iodide. Owing to these synergistic effects, the aqueous Zn‐I2 batteries with the I2@PFC‐72‐Co cathode exhibit excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Smart electroactive materials that can dynamically regulate stem cell fate without external stimuli have fascinated increasing attention. Meanwhile, noninvasive electrical stimulation has emerged as a less restrictive approach, generating considerable interest in its potential biomedical applications. The intricate interplay between cells and materials within complex microenvironments includes encompassing substrate response, ion exchange, and membrane potential alterations. However, the mechanisms by which smart materials influence stem cells have yet to be fully elucidated. Herein, electrospinning technology is utilized to fabricate bone‐mimicking microenvironments comprising disordered and highly oriented polyvinylidene fluoride (PVDF) nanofibers. The aligned annealed PVDF (AA) and random annealed PVDF (RA) membranes present high fractions of β‐phase. By comparing the osteogenic ability, calcium activity, and F‐actin distribution of bone marrow‐derived mesenchymal stem cells (BMSCs) cultured with these PVDF nanofibers, it is proposed that the stem cells autonomously regulate their differentiation by remodeling the cytoskeleton on the electrospun membranes. Electrical stimulation, more adhesion area, and active calcium influx support the greater osteogenesis of BMSCs on RA than AA. This mechanism can provide a basic theory for the design and preparation of bone tissue engineering scaffolds and contribute to the further study of cells and microenvironments. [ABSTRACT FROM AUTHOR]

Highly sensitive flexible pressure sensors are extensively investigated for various applications, such as electronic skin, human physiological monitoring, and artificial intelligence. However, traditional fabrication technologies are hard to realize the large‐area and mass production of wearable sensing devices. Current trend of miniaturization, systematization, and multifunction has raised the problems of total energy consumption, frequent charging, and reduced usage time. These issues have hindered the progress of wearable sensing electronics. In the light of nanomaterial design, mass production, and facile manufacturing, electrospun piezoelectric pressure sensors offer the best properties of self‐powering, breathability, stretchability, and flexibility, providing ideal interfacing platforms for smart wearables. Tremendous advances have been achieved recently in the high sensitivity, piezoelectric output, composite optimization, and nano‐/microstructure design of nonwoven nanofiber membranes. Nevertheless, how to fulfill real textile‐level integration in consideration of biocompatibility, integration, wearability, geometrical design, multifunction, and systematization remains a big challenge. Therefore, recent progress of piezoelectric pressure sensors from electrospun nanofibers to their fabrics is comprehensively summarized. Plentiful strategies, structure designs, and underlying mechanisms that boost the piezoelectric properties are discussed. Lastly, the challenges and possible solutions for the future electrospinning‐based pressure sensing systems are proposed. [ABSTRACT FROM AUTHOR]

In the present study, we designed and prepared multilayer NiO@Co3O4 hollow spheres decorated with graphene quantum dots (NiO@Co3O4@GQDs) through a rational solvothermal treatment. The decoration of the GQDs endowed the hybrid structure with excellent electrochemical behaviors in lithium-ion batteries (LIBs) and supercapacitors (SCs). The core–shell NiO@Co3O4 hollow structure was designed based on the stepwise lithium storage mechanism (first in the Co3O4 shell and then in the NiO core). The carboxyl-functionalized GQDs led to reduced interfacial resistance and increased surface area for electrochemical reactions. The high polarity of the carboxyl functionalized GQDs also showed a strong affinity to the Li+ in LIBs and K+/OH− in SCs. As an anode for LIBs, it demonstrated a large reversible capacity of 1158 mA h g−1 (NiO@Co3O4 contribution: ∼1327 mA h g−1) after 250 cycles at 0.1 A g−1. As a SC cathode, it held an impressive high specific capacitance of 1361 F g−1 (748.5 C g−1) at 1 A g−1, and retained 76.4% capacitance after 3000 cycles. Moreover, the assembled all-solid-state asymmetric supercapacitors (ASCs) (NiO@Co3O4@GQDs//AC) could deliver an energy density of 38.44 W h kg−1 and a superior cyclability (84.3% retention after 10 000 cycles). [ABSTRACT FROM AUTHOR]

Developing an intelligent wearable system is of great significance to human health management. An ideal health-monitoring patch should possess key characteristics such as high air permeability, moisture-wicking function, high sensitivity, and a comfortable user experience. However, such a patch that encompasses all these functions is rarely reported. Herein, an intelligent bionic skin patch for health management is developed by integrating bionic structures, nano-welding technology, flexible circuit design, multifunctional sensing functions, and big data analysis using advanced electrospinning technology. By controlling the preparation of nanofibers and constructing bionic secondary structures, the resulting nanofiber membrane closely resembles human skin, exhibiting excellent air/moisture permeability, and one-side sweat-wicking properties. Additionally, the bionic patch is endowed with a high-precision signal acquisition capabilities for sweat metabolites, including glucose, lactic acid, and pH; skin temperature, skin impedance, and electromyographic signals can be precisely measured through the in situ sensing electrodes and flexible circuit design. The achieved intelligent bionic skin patch holds great potential for applications in health management systems and rehabilitation engineering management. The design of the smart bionic patch not only provides high practical value for health management but also has great theoretical value for the development of the new generation of wearable electronic devices., (© 2023 Wiley‐VCH GmbH.)