By Neha MathurNov 15 2022Reviewed by Aimee Molineux In a recent study published in Science Advances, researchers proposed a novel approach to develop flexible and biodegradable electronics called MycelioTronics, which could substitute for electronic substrate material.
Biodegradable printed circuit boards are unavailable, and most graphene and carbon-based biomaterials still incorporate unsustainable substrates. Conventional integrated circuits that take up the highest proportion of the mass of PCBs used in mobiles use metals, ceramics, and polymers. There is an urgent need for biodegradable ICs based on plant-based materials, yielding entirely transient electronics, including biodegradable circuit elements.
These skins, composed of living mycelium, were saturated with water and yielded final skins after additional compressing and drying. Further optimizing the growth conditions could accelerate and stabilize this process substantially. Nonetheless, the team achieved a maximum of five subsequent harvests from one growing medium over six weeks with sufficient mycelium skin yield of good quality.
Related StoriesThe researchers achieved the untethered operation of a standalone circuit directly incorporating a mycelium battery, a capacitive sensor, and other necessary communication modules. For biodegradable and sustainable batteries, mycelium skin soaked up large amounts of liquid in combination with a highly ion-conducting electrolyte solution, yielding a flexible membrane.
The battery supplies a high operating current of approximately two milli-ampere under standard operation and ~13.5 mA during data transmission to the circuit. When an object like a finger approached the sensor, its charging altered as the finger acted as a parasitic capacitance, resulting in distinct changes in sensor capacitance. In addition to proximity sensing, they also demonstrated the sensor’s aspiration sensing capabilities.