Flexible strain sensors based on MWCNTs/rGO hybrid conductive networks for human motion detection and thermal management

As technology continues to advance, multifunctional flexible electronic devices for monitoring human health and managing thermal conditions have garnered considerable attention. Nevertheless, achieving a balance between a wide strain sensing range and high sensitivity remains a considerable challenge. Herein, PDA/PEBA/MWCNTs/rGO (PPMr) sensors were fabricated by vacuum-assisted filtration of ultrasonically mixed multi-walled carbon nanotubes (MWCNTs) and reduced graphene oxide (rGO) loaded on polydopamine-modified PEBA nanofiber membranes. This sensor has a broad range of strain detection capabilities (0–127 % strain), high sensitivity (GF = 42), response/recovery times of 600/500 ms, and over 8000 cycles of stability. At the same time, this sensor also exhibits outstanding photothermal conversion capability (reaching 75.6 °C at 100 mW/cm 2 ), electrothermal conversion capability (up to 82.2 °C at 8 V), and excellent photothermal/electrothermal synergistic conversion capability (reaching 78.9 °C at 100 mW/cm 2 and 4 V). This strain sensor is noteworthy for its outstanding performance, as it can detect body movements across a wide range of strain, such as elbow joint movements, as well as subtle physiological signals like pulse waves. This capability highlights its significant potential for applications in human health monitoring and thermal management.