Structured carbon nanotube–elastomer nanocomposites with a morphing–contact mechanism for an advanced underwater perception warning system

Abstract

Underwater sensors with high sensitivity in danger sensing and warning ability have become an urgent requirement for various underwater applications. We prepared flexible, transferable, and tailorable conductive Janus films through the morphology manipulation of an air–water interface. Herein, the interface-guided elastic conductive Janus films were rationally designed to construct floating underwater sensors, in which a bilayer structure was integrated with the Janus films in self-supported and supported forms. The as-prepared underwater sensor achieved both high sensitivity sensing via 3D morphing and depth/intensity threshold warning ability through dynamic film contacts. When the depth or flow field strength was stronger than a preset threshold, the morphing film could contact with the supported film, resulting in the reversal of the current signal for danger warning. Furthermore, a wearable sensor was designed to efficiently monitor a swimmer who dives to unsafe depths or struggles with drowning risk.