Electrospun Thermoplastic Polyurethane Fibrous Membrane Decorated with MXene/Carbon Black for Dual-Mode Human Movement Monitoring and Energy Harvesting

Abstract

Conductive fiber membranes have received widespread attention due to their excellent physical and chemical properties. However, developing conductive fiber membranes for both strain sensing and energy harvesting remains a challenge. Herein, a novel thermoplastic polyurethane (TPU)/polydopamine (PDA)/MXene/carbon black (CB) (TPMC) conductive fibrous membrane is developed by combining electrospinning and layer-by-layer dip-coating processes. The TPMC fibrous membrane can be used as a component of strain sensors and triboelectric nanogenerators (TENG) to achieve dual-mode human motion detection and energy harvesting. The strain sensor boasts a wide operating range (0.5%-195%), excellent sensitivity (with a gauge factor (GF) up to 54 at 50% strain and maximum GF of 6.5×10⁴), fast response (80 ms) and excellent cycle durability (over 10 000 cycles), making it possible to detect slight or heavy human activities under various conditions effectively. Additionally, a single-electrode TENG utilizing the TPMC membrane achieves an output voltage of 115 V, a current of 0.8 µA, and a power density of 68 mW m⁻², also serving as a self-powered sensor for various movements. The excellent dual-mode sensing and energy harvesting properties make it promising for future high-performance wearable devices.