- Titel
- Leaftronics: Harnessing Leaf-derived Lignocellulose Scaffolds for Sustainable Electronics
- Zitierfähige Url:
- https://nbn-resolving.org/urn:nbn:de:bsz:14-qucosa2-979886
- Erstveröffentlichung
- 2025
- Datum der Einreichung
- 21.05.2024
- Datum der Verteidigung
- 05.09.2024
- Abstract (EN)
- This research work proposes that quasi-fractal lignocellulose structures present in leaves, when extracted, can serve as mechanically robust, biodegradable natural scaffolds capable of taking up solution processed functional materials and coalescing them into extraordinarily well performing substrates and electrodes. Facile fabrication techniques are developed here that yield flexible, transparent, and biodegradable substrates with mean surface roughness below 3 nm. It is shown that these substrates are not only suitable for the fabrication of state-of-the-art physical vapor-deposited optoelectronic devices, but also function well as substrates for flexible thin film printed transistors and batteries. Additionally, it is shown that these substrates can be optimized for use as commercially viable PCBs and can sustain industrially relevant temperatures needed for soldered circuitry. The recyclability, biodegradability, and total carbon footprint of these substrates is also subsequently studied. Apart from substrate applications, a novel technique to coat these lignocellulose scaffolds with silver and copper while leaving the interstitial pores unblocked is also developed. This results in porous, freestanding, and highly conducting quasi-transparent biopolymer-based meshes that make excellent transparent electrodes for optoelectronic applications. This thesis also reports the first experiments performed that demonstrate the efficacy of such nature-derived conducting scaffolds for the oligodynamic disinfection of contaminated water. This new paradigm, with its myriad sustainable possibilities, has been coined ‘Leaftronics’.
- Freie Schlagwörter (EN)
- Leaftronics, biomimetics, biodegradable substrates, circular electronics, lignocellulose
- Klassifikation (DDC)
- 621
- Klassifikation (RVK)
- ZN 3499
- GutachterIn
- Prof. Dr. Karl Leo
- Prof. Dr. Björn Lüssem
- Prof. Dr. Stefan Mannsfeld
- BetreuerIn Hochschule / Universität
- Prof. Dr. Karl Leo
- Den akademischen Grad verleihende / prüfende Institution
- Technische Universität Dresden, Dresden
- Version / Begutachtungsstatus
- publizierte Version / Verlagsversion
- URN Qucosa
- urn:nbn:de:bsz:14-qucosa2-979886
- Veröffentlichungsdatum Qucosa
- 05.08.2025
- Dokumenttyp
- Dissertation
- Sprache des Dokumentes
- Englisch
- Lizenz / Rechtehinweis
CC BY-NC 4.0- Inhaltsverzeichnis
Abstract i 1 Introduction and Motivation ...................................................................................................... 16 2 Fundamentals ............................................................................................................................... 20 2.1 Biopolymer-based substrates in electronics ............................................................................. 20 2.2 Nature-derived fractals in electronics ....................................................................................... 27 2.3 Natural fractals within leaves ................................................................................................... 30 3 Materials and Methods ................................................................................................................ 33 3.1 Lignocellulose scaffold extraction from natural leaves ........................................................... 33 3.1.1 Method 1: Alkaline etching ............................................................................................... 33 3.1.2 Method 2: Controlled fermentation ................................................................................... 35 3.2 Solution/Ink synthesis .............................................................................................................. 35 4 Results and Discussion ................................................................................................................. 37 4.1 Leaf-derived scaffolds as biodegradable substrates ..................................................... 38 4.1.1 Lignocellulose scaffold coating ........................................................................................ 38 4.1.2 Substrate exfoliation .......................................................................................................... 44 4.1.3 Thermal, mechanical, and optical characterization ........................................................... 52 4.1.4 Substrate biodegradation ................................................................................................... 59 4.1.5 Biocompatibility ................................................................................................................ 61 4.1.6 Ink testing .......................................................................................................................... 64 4.1.7 Organic electrochemical transistors (OECTs) on lignocellulose substrates ..................... 66 4.1.8 Organic Photodiodes (OPDs) on lignocellulose substrates ............................................... 70 4.1.9 Soldered circuitry on lignocellulose substrates ................................................................. 74 4.1.10 Component recovery and substrate upcycling .................................................................. 79 4.1.11 Lignocellulose substrates as Moisture-enabled Energy Generators (MEGs) .................... 84 4.1.12 Rechargeable Zn-Br cells .................................................................................................. 93 4.1.13 Carbon footprint calculations .......................................................................................... 105 4.2 Leaf-derived scaffolds as metallized electrodes .......................................................... 110 4.2.1 Thermomechanical, electrical, and optical characterization ........................................... 115 4.2.2 Copper plating ................................................................................................................. 121 4.2.3 Metallized lignocellulose scaffolds for water purification .............................................. 123 5 Conclusion and Outlook ............................................................................................................ 130 5.1 Conclusion ...................................................................................................................... 130 5.2 Outlook ........................................................................................................................... 132 5.2.1 Life-cycle assessment ...................................................................................................... 132 5.2.2 Other leaf species for harvesting lignocellulose scaffolds .............................................. 135 5.2.3 Applications in bio-inspired neuromorphic computing .................................................. 137 5.2.4 Lignocellulose scaffolds for cell growth ......................................................................... 139 5.2.5 Organic light-emitting diodes .......................................................................................... 140 References ...................................................................................................................................... 141 Abbreviations ................................................................................................................................ 167 List of Figures ................................................................................................................................ 169 Acknowledgements ....................................................................................................................... 176 Erklärung ....................................................................................................................................... 178 Curriculum vitae ........................................................................................................................... 179