A cost-effective, accessible Reduced Graphene Oxide (rGO) multifunctional wearable sensor via transfer printing

Abstract

Tattoo-like sensors represent a class of emerging wearable devices that can be directly applied to flexible and stretchable surfaces, like the human skin, without causing any peeling and dusting. Currently, available tattoo sensors are typically applied through a thin metal coating or conducting particle infiltrated nanofibrous network, which would interfere with the users’ sense of touch. Herein, we report flexible tattoo-like sensor based on laser-induced reduced graphene oxide (rGO) that can be easily transferred printed onto flexible surfaces with minimal sensory interference. Via direct writing, the rGO can be designed with arbitrary shape and geometry on a liquid surface. The rGO can then be transferred conformally onto a flexible surface. This rGO-based wearable sensor is capable of sensing external stimuli, such as applied tactile pressure. The ease of application, the thin form factor, and flexible nature of the rGO-based tattoo sensor ensured device can perform reliably, while providing user comfort and minimal sensory interference.