An Edible Supercapacitor Based on Zwitterionic Soy Sauce‐Based Gel Electrolyte

• Published in: Advanced functional materials Vol. 34; no. 6
• Main Authors: Durukan, Mete Batuhan, Keskin, Deniz, Tufan, Yiğithan, Dincer, Orcun, Cicek, Melih Ogeday, Yildiz, Bayram, Çınar Aygün, Simge, Ercan, Batur, Unalan, Husnu Emrah
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01-02-2024
• Subjects: Cutting equipment; edible; Electrolytes; Electronic implants; Electronics; Energy storage; gel electrolytes; Gels; Hydroxyethyl celluloses; Internet of Things; Ion currents; Medical electronics; Power sources; Sauces; Soy sauce; Supercapacitors; zwitterionic; Zwitterions
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202307051

With rapid technological developments, the use and reliance on small and miniaturized electronics have increased significantly. Prevalent power sources used in wearable and implantable devices are based on potentially toxic materials. This creates massive environmental problems and generates waste that requires novel and sustainable solutions in the Internet of Things era. Alongside newly developed biodegradable and implantable devices, edible and ingestible electronic devices have emerged to create a niche and sustainable solution. To realize these devices, energy sources must also be edible and ingestible. Here, zwitterionic and edible gel electrolytes are produced using hydroxyethyl cellulose and commercial soy sauce (shoyu) for superior ionic conductivity, providing a favorable environment for L929 proliferation. These edible gels are combined with carbon electrodes to fabricate edible supercapacitor devices, resulting in an ideal double‐layer capacitance. These gels have been discovered to operate at sub‐zero temperatures and possess anti‐drying properties. Introducing an edible soy sauce‐based gel with impressive ionic performance provides a promising alternative to conventional energy storage devices, enabling the advancement of cutting‐edge ingestible healthcare devices and environmentally friendly electronics.
An edible supercapacitor using commercial soy sauce‐based gel electrolyte is fabricated. Developed gel electrolyte are shown to allow cellular growth, indicating its biocompatibility. The designed gel electrolyte and fabricated supercapacitor dissolve in the simulated gastric fluid within 40 minutes, showing biodegradability. The edible supercapacitors show a maximum specific capacitance of 3.75 F g⁻¹ and demonstrate a capacitance retention of 86.5% after 10 000 cycles. The edible supercapacitors have freezing tolerance and anti‐drying abilities.