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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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Toward Sustainable, High‐Performance, and Scalable On‐Chip Biopower: Microbial Biobatteries with 3D‐Printed Stainless Steel Anodes and Spore‐Based Biocatalysts
The rapid proliferation of the Internet of Things (IoT) necessitates compact, sustainable, and autonomous energy sources for distributed electronic devices. Microbial fuel cells (MFCs) offer an eco‐friendly alternative by converting organic matter into electrical energy using living micro‐organisms. However, their integration into microsystems faces significant challenges, including incompatibility with microfabrication, fragile anode materials, low electrical conductivity, and compromised microbial viability. Here, this study introduces a microscale biobattery platform integrating laser powder bed fusion‐fabricated 316L stainless steel anodes with resilient, spore‐formingBacillus subtilisbiocatalysts. The 3D‐printed gyroid scaffolds provide high surface‐to‐volume ratios, submillimeter porosity, and tunable roughness, enhancing microbial colonization and electron transfer. The stainless steel ensures mechanical robustness, chemical stability, and superior conductivity.Bacillus subtilisspores withstand harsh conditions, enabling prolonged storage and rapid, on‐demand activation. The biobattery produces 130 μW of power, exceeding conventional microscale MFCs, with exceptional reuse stability. A stack of six biobatteries achieves nearly 1 mW, successfully powering a 3.2‐inch thin‐film transistor liquid crystal display via capacitor‐assisted energy buffering, demonstrating practical applicability. This scalable, biologically resilient, and fabrication‐compatible solution advances autonomous electronic systems for IoT applications.
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- Award ID(s):
- 2410431
- PAR ID:
- 10617877
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Energy and Sustainability Research
- ISSN:
- 2699-9412
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/aesr.202500199
