Highly stretchable and microporous hybrid film-based electronic skins for biomimetic devices and smart wearables

With the rapid development of biomimetic devices and smart wearables, there is increasing potential for electronic skin (E-skin) applications in the fields of space debris retrieval, medical diagnosis, and rehabilitation. Here, we report the stretch/temperature-sensitive (S/T-S) and pressure-sensitive (P-S) E-skins based on a highly stretchable and microporous carbon nanotube/graphene/thermoplastic polyurethane hybrid film. The gauge factors (GFs) of the S/T-S E-skin are 12.19 and 635.03 in the ε ranges of 0%–340% and 340%–480%, respectively. In addition, the prestretching process largely improves its repeatability during the stretching-releasing cycles. The P-S E-skin has a GF value of 1.79 kPa −1 in the pressure ranges of 5–20,005 Pa. Given their excellent performance, the E-skins are integrated into a biomimetic frog tongue for the detection of environmental temperature, telescopic, and tactile signals. Furthermore, a machine learning-combined foot posture analysis system is also proposed with a high recognition accuracy of 96.2%.