Bio-inspired Anthozoan-like Design for the Fabrication of Biodegradable Omnidirectional Intelligent Sensing Carpets

Abstract

High-performance flexible pressure sensors are crucial electronic components for a diverse array of Internet of Things applications. In real-world scenarios, flexible sensors demonstrate significant promise by effectively detecting subtle anomalous signals from any direction. This study presents a straightforward preparation process for a biodegradable omnidirectional intelligent sensing carpet, inspired by the multi-contact structure of anthozoans. The developed sensor is constructed from conductive polyaniline (PANI) that has been modified through in situ polymerization on carbon nanotubes (CNTs) multi-contact structured materials (CNTs@PANI), combined with an eco-friendly bio-based polyurethane urea (BDPU) flexible substrate. This unique combination enables omnidirectional and stable pressure detection, making it suitable for intelligent monitoring applications of home carpets. The resulting smart carpet based on a pressure sensor exhibits remarkable performance characteristics, including high sensitivity, low monitoring limit, and rapid response and recovery times. Importantly, the sensor notably demonstrates omnidirectional responsiveness, effectively detecting signals from multiple directions while ensuring consistent sensing performance even after self-healing during subsequent use. This sensor also supports the recovery and reuse of the CNTs@PANI conductive materials within it. This innovative, efficient, and versatile sensor is anticipated to find widespread application in multi-scenario monitoring systems.

Graphic Abstract

Inspired by the multi-contact structures of anthozoans, this study presents a biodegradable omnidirectional intelligent sensing carpet, incorporating conductive polyaniline modified via in situ polymerization on carbon nanotubes, and featuring a flexible substrate made from bio-based polyurethane urea.

Keywords

CNTs / Polyaniline / Polyurethane / Sensors / Degradable / Self-healing

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Funding

National Natural Science Foundation of China(No. 22478160)

RIGHTS & PERMISSIONS

Donghua University, Shanghai, China