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Continuous monitoring of bio/physiological signals will play an essential role in personalized, patient‐centric medicine in the future healthcare industry. One of the challenges involves providing a sustainable, energy‐efficient operation for long‐term monitoring devices. The current technology based on power sources requires periodic replacement. Here, a hybrid film composed of a layer of piezoelectric nanowire (PVDFHFP) and a layer of microgel (pNIPAM‐APBA) is presented that continuously monitors glucose, does not rely on enzymes, is self‐charging, and decouples changes in read‐out signals due to glucose detection from the force is applied to activate self‐charging. By characterizing self‐charging/discharging properties, the operation and sensing mechanism for the nanowire/microgel hybrid film are proposed. A reasonable sensitivity of 70 mV mm−1 with a high linearity value of R2 = 0.9956 is observed. This work demonstrates the potential for use in a self‐charging wearable platform that enables continuous monitoring of bio/physiological signals. [ABSTRACT FROM AUTHOR]

Herein, a self‐charging mechanism of rechargeable aluminum (Al) batteries with Chevrel phase molybdenum sulfide (Mo6S8) cathode is reported. The results unambiguously reveal that the self‐charging is a spontaneous disproportionation of Al intercalated Mo6S8 originated from the dynamic shift of Al between occupied sites during Al intercalating and resting. The theoretical study indicates that the fully Al intercalated Mo6S8 in the format of Al4/3Mo6S8 is kinetically accessible driven by electrochemical overpotential but thermodynamically unstable due to the repulsion between Al3+ cations. This mechanism is a true self‐charging with no input of any form of energy, thus distinctly superior to the previously reported self‐charging mechanisms. Based on this discovery, a semi‐flow AlMo6S8 battery is designed and demonstrated with long‐lasting discharge capability and high capacity. [ABSTRACT FROM AUTHOR]

In recent years, the development of implantable bioelectronics has garnered significant attention. With the continuous advancement of IoT and information technology, implantable bioelectronics can be utilized more effectively for health monitoring to enhance treatment outcomes, reduce healthcare costs, and improve quality of life. Implantable energy storage devices have been widely studied as critical components for energy supply. Conventional power sources are bulky, inflexible, and potentially contain materials that are dangerous to the body. Meanwhile, human tissues are soft, flexible, dynamic, and closed, which puts new requirements on energy storage devices to improve the safety, stability, and matching of implantable batteries or supercapacitors. Herein, recent advances in state‐of‐the‐art nonconventional power options for implantable electronics, specifically biocompatible, miniaturized, stretchable/deformable, biodegradable/bioresorbable, edible, and injectable energy storage devices, are reviewed in this paper. The material strategy and architectural design of the next‐generation implantable energy storage device are discussed, including the selection principle of electrolytes, the all‐in‐one structure design strategy, and the way to realize self‐charging. Finally, the challenges and prospects of emerging design strategies toward developing next‐generation implantable batteries and supercapacitors for the future are put forward. [ABSTRACT FROM AUTHOR]

The water vapor exhaled by the human body can severely accelerate the charge dissipation of a polypropylene (PP)‐based medical mask, thereby reducing the electrostatic adsorption efficiency to cause infection. To solve this problem, a new type of polyvinyl alcohol (PVA)‐based medical mask through electrostatic spinning to replace the PP melt‐blown layer, which has self‐charging and charge retention performance in a high humidity environment is fabricated. The PVA is rich in hydroxyl groups, which can spontaneously form hydrogen bonds with water vapor molecules exhaled by the human body and fix water molecules to increase the triboelectricity. By analyzing the electrical output performance of PVA‐based triboelectric nanogenerator (TENG), it is shown that the short circuit current is ≈26 times larger than that of PP‐based TENG in 95% relative humidity (RH). Moreover, PVA has a strong charge storage capacity and self‐charging performance, as determined by hand touching under a high humidity environment. The static dissipation rate of PVA is 1.4 times lower than that of PP at a 95% RH. In comparison with PP‐based medical masks, PVA‐based medical masks have a high humidity resistance and self‐charging performance and can be easily recharged in situ by hand slapping without taking it off for many times. [ABSTRACT FROM AUTHOR]

Smart wearable electronics that are fabricated on light‐weight fabrics or flexible substrates are considered to be of next‐generation and portable electronic device systems. Ideal wearable and portable applications not only require the device to be integrated into various fiber form factors, but also desire self‐powered system in such a way that the devices can be continuously supplied with power as well as simultaneously save the acquired energy for their portability and sustainability. Nevertheless, most of all self‐powered wearable electronics requiring both the generation of the electricity and storing of the harvested energy, which have been developed so far, have employed externally connected individual energy generation and storage fiber devices using external circuits. In this work, for the first time, a hybrid smart fiber that exhibits a spontaneous energy generation and storage process within a single fiber device that does not need any external electric circuit/connection is introduced. This is achieved through the employment of asymmetry coaxial structure in an electrolyte system of the supercapacitor that creates potential difference upon the creation of the triboelectric charges. This development in the self‐charging technology provides great opportunities to establish a new device platform in fiber/textile‐based electronics. [ABSTRACT FROM AUTHOR]

Keywords: fiber electronics; self-charging; supercapacitors; triboelectric energy generators EN fiber electronics self-charging supercapacitors triboelectric energy generators 1 1 1 03/28/20 20200324 NES 200324 In article number 1908479, Geon-Hyoung An, SeungNam Cha, and co-workers develop a hybrid smart fiber that exhibits spontaneous energy generation and storage process within a single fiber platform. The asymmetric coaxial structure, consisting of a triboelectric energy generator in the outer shell and a supercapacitor at the core, creates a triboelectric potential difference and self-charging process within the fiber device without any additional electric connection. Fiber electronics, self-charging, supercapacitors, triboelectric energy generators. [Extracted from the article]