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This study unveils a pioneering yet straightforward approach to creating a moist-electric generator, using paper as the primary substrate and integrating bacterial endospores within it. The distribution of these endospores is meticulously regulated by the paper's inherent capillary action. The functional groups present on the endospores enhance moisture absorption and facilitate ion dissociation, resulting in a pronounced potential gradient driven by the variation in water content and endospore concentration. To augment water capture efficiency, a paper-based Janus layer combining hydrophobic and hydrophilic properties is applied atop the paper-based moist-electric generator. This dual-sided membrane excels in moisture condensation from the atmosphere and ensures unidirectional water transport to the generator, thus ensuring substantial electrical output even under low relative humidity conditions. This research not only addresses the challenges of power generation in wearable paper-based devices but also heralds new pathways for the development of autonomous, cost-effective, and eco-friendly energy solutions for wearable technologies.
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A Paper‐Based Wearable Moist–Electric Generator for Sustained High‐Efficiency Power Output and Enhanced Moisture Capture
Abstract Disposable wearable electronics are valuable for diagnostic and healthcare purposes, reducing maintenance needs and enabling broad accessibility. However, integrating a reliable power supply is crucial for their advancement, but conventional power sources present significant challenges. To address that issue, a novel paper‐based moist–electric generator is developed that harnesses ambient moisture for power generation. The device features gradients for functional groups and moisture adsorption and architecture of nanostructures within a disposable paper substrate. The nanoporous, gradient‐formed spore‐based biofilm and asymmetric electrode deposition enable sustained high‐efficiency power output. A Janus hydrophobic–hydrophilic paper layer enhances moisture harvesting, ensuring effective operation even in low‐humidity environments. This research reveals that the water adsorption gradient is crucial for performance under high humidity, whereas the functional group gradient is dominant under low humidity. The device delivers consistent performance across diverse conditions and flexibly conforms to various surfaces, making it ideal for wearable applications. Its eco‐friendly, cost‐effective, and disposable nature makes it a viable solution for widespread use with minimal environmental effects. This innovative approach overcomes the limitations of traditional power sources for wearable electronics, offering a sustainable solution for future disposable wearables. It significantly enhances personalized medicine through improved health monitoring and diagnostics.
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- PAR ID:
- 10543669
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 20
- Issue:
- 50
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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