A Self-Healable Bifunctional Electronic Skin

Abstract

For the mimicry of human skin, one of the challenges is how to detect and recognize different stimulus by electronic device, while still has the ability of skin self-recovery at the same time. Because of the excellent elasticity and flexibility, strong self-healing ability, in this paper, we reported a bifunctional self-healing e-skin with polyurethane (PU) and polyurethane@multiwalled carbon nanotubes (PU@CNT) as the sensing materials by integrating a resistance temperature sensor on top of a capacitive pressure sensor on the same flexible cellulose nanocrystals@carboxylated nitrile rubber@polyethylenimine (CNC@XNBR) substrate. Studies found that each type of sensor exhibited fast and superior response to only the target stimuli. Meanwhile, due to the self-recovery properties of PU and CNC@XNBR, as-fabricated e-skin has the self-healing ability after damage and remains excellent sensitivity to temperature and pressure after healing. A 5 × 5 device array was also fabricated, which can simultaneously image the pressure and temperature distribution.