Abstract Extensive research into green technologies is driven by the worldwide push for eco‐friendly materials and energy solutions. The focus is on synergies that prioritize sustainability and environmental benefits. This study explores the potential of abundant, non‐toxic, and sustainable resources such as paper, lignin‐enriched paper, and cork for producing laser‐induced graphene (LIG) supercapacitor electrodes with improved capacitance. A single‐step methodology using a CO2laser system is developed for fabricating these electrodes under ambient conditions, providing an environmentally friendly alternative to conventional carbon sources. The resulting green micro‐supercapacitors (MSCs) achieve impressive areal capacitance (≈7–10 mF cm−2) and power and energy densities (≈4 μW cm‐2and ≈0.77 µWh cm−2at 0.01 mA cm−2). Stability tests conducted over 5000 charge–discharge cycles demonstrate a capacitance retention of ≈80–85%, highlighting the device durability. These LIG‐based devices offer versatility, allowing voltage output adjustment through stacked and sandwich MSCs configurations (parallel or series), suitable for various large‐scale applications. This study demonstrates that it is possible to create high‐quality energy storage devices based on biodegradable materials. This development can lead to progress in renewable energy and off‐grid technology, as well as a reduction in electronic waste.
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A Transient Spore‐Forming Microbial Fuel Cell with Extracellularly Biosynthesized Tin Oxide Nanoparticles for Powering Disposable and Green Papertronics
Abstract Transient electronics, which can operate only for short‐lived applications and then be eco‐friendly disintegrated, create opportunities in environmental sensing, healthcare, and hardware security. Paper‐based electronics, or papertronics, recently have rapidly advanced the physically transient device platform because paper as a foundation offers an environmentally sustainable and cost‐effective option for those increasingly pervasive and fast‐updated single‐use applications. Paper‐based power supplies are indispensable to realize a fully papertronic paradigm and are a critical enabler of environmentally benign power solutions. Microbial fuel cells (MFCs) hold great potential as power sources for such green papertronic applications. This work reports the design, operation, and optimization of a high‐power papertronic MFC by biosynthesizing microbe‐mediated tin oxide nanoparticles (SnO2NPs) on dormant Bacillus subtilis endospores. They form an electrical conduit that improves electron harvesting during the spore germination and power generation. The MFC is packaged in a sub‐microporous alginate to minimize the potential risk of bacteria leakage. Upon the introduction of water, the paper‐based MFC generates a significantly enhanced power density of 140 µW cm−2, which is more than two orders of magnitude greater than their previously reported counterparts. Six MFCs connected in series generate more than sufficient power to run an on‐chip, light‐emitting diode.
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- Award ID(s):
- 2246975
- PAR ID:
- 10505532
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Sustainable Systems
- Volume:
- 8
- Issue:
- 2
- ISSN:
- 2366-7486
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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