Piezoresistive/Piezoelectric Hybrid Pressure Sensors via Towel Fabric Coated With PDMS/CNTs/PPy/ZnO

The integration of textile-based wearable electronic systems has garnered significant attention due to their potential to enhance the comfort and safety of electronic devices when incorporated into clothing. This study introduces a fabrication strategy for a versatile e-textile utilizing a sequential combination of polydimethylsiloxane (PDMS), functionalized carbon nanotubes (CNTs), and polypyrrole (PPy) integrated onto a cotton towel fabric adorned with zinc oxide (ZnO) nanoplate structures. The growth of ZnO nanoplate structures on the towel fabric surface enhances the fabric's roughness and pressure sensitivity. Additionally, the application of a PDMS coating onto the conductive towel fabric provides adhesion for the conductive layer, imparts superhydrophobicity to the sensors, and enhances the stability of the pressure-sensitive device. The resulting sensor demonstrates a broad sensing range (0-225 kPa) coupled with heightened sensitivity (122 kPa (-1) in low-pressure regions), achieving a harmonious balance between working range and sensitivity. Of particular significance, this sensor is capable of monitoring various human motions such as wrist, elbow, and knee bending, as well as activities like walking and jumping, in addition to capturing physiological signals like swallowing. Furthermore, the sensors exhibit self-powering capabilities, manifesting a notable 1. 47-V peak-to-peak voltage from renewable sources like human movement, eliminating the need for external power or frequent battery replacement and enabling flexible design. In conclusion, this multifunctional e-textile exhibits exceptional sensing and energy harvesting characteristics, while its straightforward manufacturing process underscores its potential for diverse applications within the domain of wearable technology.