An All-Silk-Derived Dual-Mode E-skin for Simultaneous Temperature–Pressure Detection

TLDR

Flexible, skin‑mimicking electronics are sought for smart interfaces and health monitoring, yet integrating multiple sensing functions remains challenging due to mutual interference. This work reports a dual‑mode temperature‑pressure e‑skin built by combining a temperature sensor and a strain sensor that both use silk‑nanofiber‑derived carbon fiber membranes. The e‑skin employs silk‑nanofiber‑derived carbon fiber membranes as passive, transparent active layers that isolate temperature and pressure signals, allowing simultaneous, precise detection. The device achieves 0.81 %/°C temperature sensitivity and a gauge factor of ~8350 at 50 % strain, enabling detection of subtle pressures and exhalation patterns, and demonstrates green, scalable fabrication suitable for human‑machine interfaces.

Abstract

Flexible skin-mimicking electronics are highly desired for development of smart human-machine interfaces and wearable human-health monitors. Human skins are able to simultaneously detect different information, such as touch, friction, temperature, and humidity. However, due to the mutual interferences of sensors with different functions, it is still a big challenge to fabricate multifunctional electronic skins (E-skins). Herein, a combo temperature-pressure E-skin is reported through assembling a temperature sensor and a strain sensor in both of which flexible and transparent silk-nanofiber-derived carbon fiber membranes (SilkCFM) are used as the active material. The temperature sensor presents high temperature sensitivity of 0.81% per centigrade. The strain sensor shows an extremely high sensitivity with a gauge factor of ∼8350 at 50% strain, enabling the detection of subtle pressure stimuli that induce local strain. Importantly, the structure of the SilkCFM in each sensor is designed to be passive to other stimuli, enabling the integrated E-skin to precisely detect temperature and pressure at the same time. It is demonstrated that the E-skin can detect and distinguish exhaling, finger pressing, and spatial distribution of temperature and pressure, which cannot be realized using single mode sensors. The remarkable performance of the silk-based combo temperature-pressure sensor, together with its green and large-scalable fabrication process, promising its applications in human-machine interfaces and soft electronics.