Flexible Broad-Range Graphene-based Piezoresistive Pressure Sensor

In recent years, there has been a considerable emphasis on the development of flexible wearable sensors as a means of enhancing quality of life through advanced technologies. One type of sensor that has garnered significant interest is the wearable flexible pressure sensor, which holds great potential for healthcare applications and monitoring human motions. In pursuit of this objective, two piezoresistive pressure sensors were created by employing Graphene nanoplates (GNPs) and polyvinylidene fluoride (PVDF) and coatings them on a commercial polyester substrate, each with different concentrations of GNPs in PVDF. Examination through scanning electron microscopy reveals a uniform coating morphology on the surface of the substrate. The sensor with a higher concentration of GNP exhibits greater sensitivity, with a value of 0.139 kP$\mathrm{a}^{-1}$ over a broad operating range of 0 to 90 kPa, and 0.114 kP$\mathrm{a}^{-1}$ within the pressure range of 90 to 200 kPa. Furthermore, the response and recovery times of the sensor are 2 ms and 4 ms, respectively. This study demonstrates a promising approach for the development of flexible wearable sensors that can be integrated into footwear to monitor plantar motion activities such as walking, jumping, and standing. As a result, this approach holds significant potential for a range of physiological activity applications.