A CMMT/APU Hydrogel-Based Triboelectric Nanogenerator for High-Precision Self-Powered Human Motion Monitoring

Developing flexible self-powered sensors capable of simultaneously converting biomechanical stimuli into electrical signals and supporting wearable motion analysis is of considerable importance for next-generation intelligent monitoring systems. In this work, a conductive montmorillonite/amphiphilic polyurethane (CMMT/APU) hydrogel-based triboelectric nanogenerator (CA-TENG) is constructed by integrating a conductive montmorillonite-modified hydrogel electrode with a contact-separation triboelectric configuration. Polytetrafluoroethylene (PTFE) and nylon are selected as the triboelectric layers, while the CMMT/APU hydrogel is employed as the flexible conductive electrode. Owing to the cooperative effect between conductive montmorillonite and the amphiphilic polyurethane network, the hydrogel exhibits good flexibility, structural stability, and mechanical adaptability, and the composition containing 5% CMMT presents the most suitable tensile performance for device fabrication. The optimized CA-TENG delivers a peak open-circuit voltage (VOC) of 777 V, a short-circuit current (I SC ) of 39 μA, and a transferred charge (Q SC ) of 250 nC, together with a maximum output power of 598 μW. Moreover, the device shows stable output under different working frequencies, separation distances, and humidity conditions, and it can effectively distinguish walking, running, jumping, and joint bending motions, demonstrating strong potential for self-powered wearable motion monitoring and biomechanical analysis.