Fully paper-integrated hydrophobic and air permeable piezoresistive sensors for high-humidity and underwater wearable motion monitoring

Paper-based electronics have attracted much attention due to their softness, degradability, and low cost. However, paper-based sensors are difficult to apply to high-humidity environments or even underwater. Here, we report a fully paper-integrated piezoresistive sensing system that exhibits flexibility, waterproofing, air permeability, and biocompatibility. This system consists of hydrophobic paper as the substrate and encapsulation layer, conductive paper with a double 'zig-zag' and dotted surface structure as the sensing layer, and silver paste films as the interconnects. The structural design of the sensing layer helps to increase the contact area in adjacent layers under pressure and further improves the pressure sensitivity. The piezoresistive system can be worn on human skin in the ambient environment, wet environment, and water for real-time monitoring of physiological signals with air permeability and waterproofing due to its hydrophobic fiber structure. Such a device provides a reliable, economical, and eco-friendly solution to wearable technologies.

Automated summary

This study presents a fully paper-integrated piezoresistive sensing system that is flexible, waterproof, air-permeable, and biocompatible. The system consists of hydrophobic paper as the substrate, conductive paper with a special surface structure as the sensing layer, and silver paste films as the interconnects. The designed sensing layer increases the contact area and enhances the pressure sensitivity. The system can be worn on human skin to monitor physiological signals in various environments, providing a reliable, economical, and eco-friendly solution to wearable technologies.