Biomimetic bilayer ionic conductive photoelectronic skin based on nano-structured photonic crystal film and flexible adhesive hydrogel for dual-signal motion detection and anti-disturbance temperature monitor

The growing interest in biological skin mimicry has greatly contributed to the creation of high-performance artificial skin. Here, inspired by the optical-electrical signal co-transmission of chameleon skins, a bilayer biomimetic ion-conductive photoelectronic skin (BIPES) was constructed by compositing the mechanochromic nano-structured silica photonic crystal film with an adhesive, flexible hydrogel by a layer-by-layer design strategy. The BIPES has a highly sensitive strain response on electrical and optical signals (GF = 3.27 at 0–100 %, Δλ/Δε = 2.1 nm %–1) and temperature response (TCR = –2.27 % °C–1 at 0–50 °C). Importantly, through the temperature insensitivity of the mechanochromic film, the BIPES not only achieved dual-signal motion detection but also achieved real-time temperature monitoring excluding strain interference. This research provides new inspiration for the construction of multi-signal combined photoelectronic skins and further exploration for advanced accurate smart wearable electronics in applications, especially in health detection for patients with non-spontaneous body-trembling.