The present work highlights an attempt of fabricating a nanocomposite by addition of multi-walled carbon nanotubes (MWCNT) as third phase into flexible ZnO-Poly(vinylidene fluoride) (ZnO-PVDF) composites. MWCNT played very important...

Aspect ratio of filler plays a crucial role to study the electrical properties of polymer based composite system. Here, we investigated the effect of filler aspect ratio on the electrical properties of zinc oxide (ZnO) incorporated poly(vinylidene fluoride) (PVDF) matrix. ZnO nanorods having different aspect ratio were synthesized by the hydrothermal technique with varying reaction time 4 to 20 hours at a fixed temperature and PVDF based nanocomposites of the respective ZnO nanorods with different wt% filler loading were fabricated. Interestingly polar‐phase fraction increased with the aspect ratio of ZnO nanorods. The nanocomposites with higher aspect ratio ZnO nanorods showed an increased energy density under same electric field and exhibited maximum open circuit AC output voltage (ie, 20 V) after the application of repeated human finger tapping. This result indicates that high aspect ratio ceramic filler provides an effective approach to enhance the dielectric, ferroelectric, energy storage, and energy harvesting performances of ceramic‐polymer nanocomposites.

In recent times, BiFeO3 (BFO) has become one of the best multifunctional materials due to its several real life applications including multiferroicity, piezoelectricity, magnetism, photovoltaics, spintronics, gas sensing and photocatalysis....

Wearable bioelectronic patches are creating a transformative effect in the health care industry for human physiological signal monitoring. However, the use of such patches is restricted due to the unavailability of a proper power source. Ideal biodevices should be thin, soft, robust, energy-efficient, and biocompatible. Here, we report development of a flexible, lightweight, and biocompatible electronic skin-cum-portable power source for wearable bioelectronics by using a processed chicken feather fiber. The device is fabricated with a novel, breathable composite of biowaste chicken feather and organic poly(vinylidene fluoride) (PVDF) polymer, where the chicken feather fiber constitutes the “microbones” of the PVDF, enhancing its piezoelectric phase content, biocompatibility, and crystallinity. Thanks to its outstanding pressure sensitivity, the fabricated electronic skin is used for the monitoring of different human physiological signals such as body motion, finger and joint bending, throat activities, and pulse rate with excellent sensitivity. A wireless system is developed to remotely receive the different physiological signals as captured by the electronic skin. We also explore the capabilities of the device as a power source for other small electronics. The piezoelectric energy harvesting device can harvest a maximum output voltage of ∼28 V and an area power density of 1.4 μW·cm–2 from the human finger imparting. The improved energy harvesting property of the device is related to the induced higher fraction of the electroactive phase in the composite. The easy process ability, natural biocompatibility, superior piezoelectric performance, high pressure sensitivity, and alignment toward wireless transmission of the captured data make the device a promising candidate for wearable bioelectronic patches and power sources.

Flexible electronic skins (e‐skins) have a wide range of applications in health monitoring, human–machine interfaces, and robotics. Herein, a novel architecture of e‐skins with a combination of multimode measurement and low‐cost implementation is proposed. A single electronic skin layer is used to integrate both the pressure and temperature sensing properties. An e‐skin membrane is first developed with poly(vinylidene) fluoride incorporated with silicon dioxide nanoparticles. When combined with electrodes, this simple architecture allows the implementation of multimode pressure and temperature sensing. This e‐skin exhibits excellent pressure sensitivity with a response time of 1.6 ms. This sensing performance can be attributed to the uniform distribution of the embedded nanoparticles, leading to an enhancement of the electroactive β phase. This e‐skin generates a voltage, from the finger movements, that can be used to detect precisely the minute changes of the finger movement. This electronic skin demonstrates the detection of a linear range of temperature which can be attributed to the phonon‐assisted hopping mechanism. A 4 × 4 pressure sensing array is demonstrated, which is able to map the inserted pressure as well as temperature stimuli. Thus, this study provides a new conceptual design for the next‐generation green electronic skins.

Confronting the depletion of fossil fuel energy as well as pollution generated from chemical batteries, associated with the increasing number of electronic equipment and the internet of things, results in a high requirement of lightweight, low cost, sustainable, and durable power devices. Currently, a flexible and self-powered piezoelectric energy harvester (PZEH) is a suitable alternative, which may be easily integrated with small electronics to realize real-time sustainable energy generation. Therefore, a novel PZEH has been fabricated at room temperature (30 C) using Al-doped ZnO (Al@ZnO) incorporated poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) nanocomposites. Al@ZnO enables nucleation of electroactive phase within PVDF-HFP (10PALZO) exhibited polarity at a much higher fraction (F[EA] >90%) compared to neat PVDF-HFP (F[EA] = 63.8%). Piezoelectric energy harvesting capability of the device has been investigated under gentle repeated human finger tapping.

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