▎ 摘 要
Highly stretchable sensors based on graphene nanoplatelet (GNP) reinforced polydimethylsiloxane (PDMS) are manufactured for human motion monitoring purposes. The strain sensing analysis shows ultra-high gauge factor (GF) values from 40 to 300 at low strain levels up to 10(6) at high deformations at tensile conditions, and a decreasing sensitivity as GNP content increases. The compressive behavior shows an initial decrease of the electrical resistance, due to the prevalence of in-plane mechanisms, followed by a stable increase, due to the prevalence of out-of-plane mechanisms. In this regard, the Electrical Impedance Spectroscopy (EIS) analysis shows an increase of the complex impedance with increasing compressive strain. The equivalent RC-LRC circuit allows to explain the electrical mechanisms governing the compressive behavior, where the LRC element denotes the contact and intrinsic resistance and the RC element the tunnelling effect. Finally, a proof of concept of human motion monitoring proves the capability of the scalable and easy-manufactured sensors to detect frowning, raising eyebrows, blinking, breathing, blowing and, even, vocal cord motion, where each phoneme follows a unique pattern, with a robust electrical response. (C) 2022 The Authors. Published by Elsevier Ltd.