Materials able to regenerate after damage have attracted a great deal of attention since the ancient times. For instance, self-healing concretes, able to resist earthquakes, aging, weather, and seawater are known since the times of ancient Rome and are still the object of research.

While several mechanically healable materials have been reported, self-healing conductors are still relatively rare, and are attracting enormous interest for applications in electronic skin, wearable and stretchable sensors, actuators, transistors, energy harvesting, and storage devices, such as batteries and supercapacitors.1 Self-healable and recyclable conducting materials have the potential to reduce electronic waste by enabling the repair and reuse of electronic components, which can extend the lifespan of electronic devices. Furthermore, they can be used for wearable electronic and biomedical devices, which are often subject to mechanical stress causing damage to their components.

Conducting polymers exhibit attractive properties that makes them ideal materials for bioelectronics and stretchable electronics, such as mixed ionic-electronic conductivity, leading to low interfacial impedance, tunability by chemical synthesis, ease of process via solution process and printing, and biomechanical compatibility with living tissues. However, they show typically poor mechanical properties and are therefore not suitable as self-healing materials.

In our group, we produced several self-healing and stretchable conductors by mixing aqueous suspensions of the conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) with other materials providing the mechanical characteristics leading to self-healing, like for instance polyvinyl alcohol (PVA), polyethylene glycol, polyurethanes and tannic acid. 2-10 In this talk, various types of self-healing will be presented and correlated with the electrical ad mechanical properties of the materials. The use of the self-healing gels and films as epidermal electrodes and other devices will be also discussed.

REFERENCES

Y. Li, X. Zhou, B. Sarkar, F. Cicoira et al., Adv. Mater. 2108932, 2022.

Y. Li, X. Li, S. Zhang, F. Cicoira et al., Adv. Funct. Mater. 30, 2002853, 2020.

Y. Li, X. Li, R. N., S. Zhang, F. Cicoira, et al. Flexible and Printed Electronics 4, 044004, 2019.

N. Rossetti, F. Cicoira et al., ACS Appl. Bio Mater. 2, 5154-5163, 2019.

C. Bodart, N. Rossetti, F. Cicoira et al. ACS Appl. Mater. Interfaces,11, 17226-17233, 2019.

S. Zhang, Y. Li, F. Cicoira et al. Adv. Electron. Mater 1900191, 2019.

S. Zhang, F. Cicoira, Adv. Mater. 29, 1703098, 2017.

X. Zhou, G. A. Lodygensky, F. Cicoira et al., Acta Biomaterialia 139, 296-306, 2022.

X. Zhou et al, Advanced Sensor Research, in press, 2023

P. Kateb et al., Flexible and Printed Electronics, in press.