A Highly Stretchable Nanofiber-Based Electronic Skin with Pressure-, Strain-, and Flexion-Sensitive Properties for Health and Motion Monitoring

TLDR

Flexible, stretchable electronic skins that mimic natural skin are valuable for motion detection, healthcare, speech recognition, and robotics. This work proposes a low‑cost fabrication strategy for a highly sensitive, stretchable electronic skin that detects dynamic and static pressure, strain, and flexion using a GO‑doped PU nanofiber membrane with a PEDOT coating. The 3‑D porous GO‑doped PU@PEDOT nanofiber substrate provides abundant contact sites, large deformation space, and reversible conductive pathways, enabling multimodal sensing with high sensitivity and a wide range. The sensor shows pressure sensitivity up to 20.6 kPa⁻¹ over 1 Pa–20 kPa, strain sensitivity up to ~550 % with >10,000‑cycle stability, and successfully monitors pulse, expression, voice, and full human motion, indicating wearable health‑monitoring potential.

Abstract

The development of flexible and stretchable electronic skins that can mimic the complex characteristics of natural skin is of great value for applications in human motion detection, healthcare, speech recognition, and robotics. In this work, we propose an efficient and low-cost fabrication strategy to construct a highly sensitive and stretchable electronic skin that enables the detection of dynamic and static pressure, strain, and flexion based on an elastic graphene oxide (GO)-doped polyurethane (PU) nanofiber membrane with an ultrathin conductive poly(3,4-ethylenedioxythiophene) (PEDOT) coating layer. The three-dimensional porous elastic GO-doped PU@PEDOT composite nanofibrous substrate and the continuous self-assembled conductive pathway in the nanofiber-based electronic skin offer more contact sites, a larger deformation space, and a reversible capacity for pressure and strain sensing, which provide multimodal mechanical sensing capabilities with high sensitivity and a wide sensing range. The nanofiber-based electronic skin sensor demonstrates a high pressure sensitivity (up to 20.6 kPa–1), a broad sensing range (1 Pa to 20 kPa), excellent cycling stability and repeatability (over 10,000 cycles), and a high strain sensitivity over a wide range (up to approximately 550%). We confirmed the applicability of the nanofiber-based electronic skin to pulse monitoring, expression, voice recognition, and the full range of human motion, demonstrating its potential use in wearable human-health monitoring systems.