Synergistic Sensing Properties of Elastic Carrier/Nano Onion Carbon Enhanced Pressure Sensor for Highly Sensitive Gait Monitoring

The self-driven sensor based on contact-separation type triboelectric nanogenerator (CS-TENG) has garnered significant attention due to its excellent compatibility with human gait characteristics at low frequencies. Conventional CS-TENGs transfer charge between two heterogeneous friction materials through passive separation caused by external forces. This article presents a novel design of an elastomeric driven structure as a carrier for the CS-TENG, aiming at mitigating hysteresis and enhancing sensor sensitivity by promoting active separation through resilience forces. The surface of the ecoflex film is roughened to increase the specific surface area of the material. More-over, the inclusion of conductive nano onion carbon (NOC) particles in the ecoflex film promotes charge accumulation on the film's surface based on the nano capacitance effect, which improves the sensitivity of the sensor. By optimizing the material and structure, the CS-TENG with the elastic driven structure (TGES) achieves remarkable performance characteristics, including high sensitivity (0.26 V/kPa in the range of 40-80 kPa and 0.17 V/kPa in the range of 80-530 kPa), excellent linearity (voltage R-2 = 0.993 and 0.989, respectively), fast response time (10 ms), and durability (more than 5000 cycles). Combined with back-end circuit design and software programming, different plantar pressure monitoring can be realized, offering significant practical value in the fields of medical and health.