An electrically and mechanically self-healing composite with pressure- and flexion-sensitive properties for electronic skin applications

Abstract

Pressure sensitivity and mechanical self-healing are two vital functions of the human skin. A flexible and electrically conducting material that can sense mechanical forces and yet be able to self-heal repeatably can be of use in emerging fields such as soft robotics and biomimetic prostheses, but combining all these properties together remains a challenging task. Here, we describe a composite material composed of a supramolecular organic polymer with embedded nickel nanostructured microparticles, which shows mechanical and electrical self-healing properties at ambient conditions. We also show that our material is pressure- and flexion-sensitive, and therefore suitable for electronic skin applications. The electrical conductivity can be tuned by varying the amount of nickel particles and can reach values as high as 40 S cm(-1). On rupture, the initial conductivity is repeatably restored with ∼90% efficiency after 15 s healing time, and the mechanical properties are completely restored after ∼10 min. The composite resistance varies inversely with applied flexion and tactile forces. These results demonstrate that natural skin's repeatable self-healing capability can be mimicked in conductive and piezoresistive materials, thus potentially expanding the scope of applications of current electronic skin systems.

Paper‐Based Electrodes for Flexible Energy Storage Devices

“…Electronic or optoelectronic components on flexible substrates enable novel applications, such as flexible display, electronic textile, artificial electronic skin, distributed sensors, etc 1, 2, 3, 4, 5, 6, 7, 8, 9. Whilst various flexible electronics are commercially available nowadays, the development of flexible energy and power sources for these devices is slow 10, 11.…”

Self-healing and self-repairing technologies

“…The latest advances in terms of artificial skin combine pressure and flexion sensitivity with mechanical self-healing [137]. It is a composite material composed of a supramolecular organic polymer with embedded nickel nano-structured micro-particles.…”

Recent Progress in Electronic Skin

“…These artificial intelligent e‐skins with diverse sensing modules can simultaneously differentiate among various physical stimuli from the complex external environment, including strain, twist, temperature, and humidity 10. The self‐healing and/or self‐powered devices are especially favorable for next‐generation multifunctional e‐skins 11. Recently, ultrathin, flexible, and multipurpose sensors with high‐density integrated circuits and other chemical or physical sensors have been developed for applications to robotics, health monitoring, and medical implant services 12…”