Electrical stimulation has demonstrated great effectiveness in the modulation of cell fate in vitro and regeneration therapy in vivo. Conventionally, the employment of electrical signal comes with the electrodes, battery, and connectors in an invasive fashion. This tedious procedure and possible infection hinder the translation of electrical stimulation technologies in regenerative therapy. Given electromechanical coupling and flexibility, piezoelectric polymers can overcome these limitations as they can serve as a self-powered stimulator via scavenging mechanical force from the organism and external stimuli wirelessly. Wireless electrical cue mediated by electrospun piezoelectric polymeric nanofibers constitutes a promising paradigm allowing the generation of localized electrical stimulation both in a noninvasive manner and at cell level. Recently, numerous studies based on electrospun piezoelectric nanofibers have been carried out in electrically regenerative therapy. In this review, brief introduction of piezoelectric polymer and electrospinning technology is elucidated first. Afterward, we highlight the activating strategies (e.g., cell traction, physiological activity, and ultrasound) of piezoelectric stimulation and the interaction of piezoelectric cue with nonelectrically/electrically excitable cells in regeneration medicine. Then, quantitative comparison of the electrical stimulation effects using various activating strategies on specific cell behavior and various cell types is outlined. Followingly, this review explores the present challenges in electrospun nanofiber-based piezoelectric stimulation for regeneration therapy and summarizes the methodologies which may be contributed to future efforts in this field for the reality of this technology in the clinical scene. In the end, a summary of this review and future perspectives toward electrospun nanofiber-based piezoelectric stimulation in tissue regeneration are elucidated.

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The shortage of fossil fuels and freshwater resources has become a serious global issue. Using solar energy to extract clean water with a photothermal conversion technology is a green and sustainable desalination method. Integrated electricity generation during the desalination process maximizes energy utilization efficiency. Herein, a solar‐driven steam and electricity generation (SSEG) system based on an all‐in‐one evaporator is prepared via a scalable technology. Carbon black is selected as the absorber for solar energy harvesting as well as the functional substance for simultaneous electricity generation. Fabric substrate with flexible structure, porous channel, and capillary effect is vital for directional brine supply, multiple solar absorption, and thermal management. The high evaporation rate (1.87 kg m−2 h−1) and voltage output (324 mV) can be achieved with an all‐in‐one device. The stable electricity output can be maintained over 40000 s. The SSEG performance remains constant after 15 operation cycles or 20 wash cycles. The integrated device balances excellent effectiveness and practicality, providing a viable path for clean desalination and electricity generation.

The increasing popularity of proton exchange membrane electrolysis technology for hydrogen production has brought attention to the electrolytic water reaction. However, the slow kinetics of the oxygen evolution reaction (OER) at the anode have great influence on the overall efficiency of the reaction. While iridium oxide shows excellent stability under acidic conditions, its OER activity still needs to be improved. Here, we synthesized two‐dimensional amorphous iridium oxide (Am‐IrO2) nanosheets with the thickness of only 6 nm by a mixed molten salt method. Such nanosheets show an ultralow overpotential of only 230 mV at 10 mA cm‐2 in 0.5 M H2SO4. The overpotential increases only 40 mV after 90 hours of the stability test at this current density. Am‐IrO2 can maintain the current density of ~400 mA cm‐2 after 120 hours of test at 1.8 V in the PEM device, demonstrating good industrial prospects. Density functional theoretical calculations show that the oxygen vacancies, together with the upshift of the O 2p band center, are responsible for the improvement of OER in Am‐IrO2.