Preparation of High-Performance BTO/PVDF Piezoelectric Pressure Sensors Based on Soybean Rhizobacteria Mimicry Using Electrostatic Spinning-Thermal Pressing Method

As an ideal flexible polymer piezoelectric material, PVDF material has a broad application prospect in pressure sensing, health monitoring, and so forth. However, traditional PVDF-based sensors usually suffer from problems such as low open-circuit voltage and slow deformation recovery. In this paper, inspired by the beaded structure of soybean rhizobial fungus, we used the strategy of combining electrostatic spinning and hot-pressing technology to construct a BTO/PVDF piezoelectric film. Specifically, PVDF is used as the substrate and doped with BTO particles to prepare a beaded internal structure. Then, hot pressing was performed to enhance the β-crystalline phase ratio of PVDF to increase the piezoelectric performance of the device. The sensors prepared by this method possess a high sensitivity of 25.23 mV/kPa in the 0–5 kPa range. The fast response time is 86 ms, and the recovery time is 57 ms, maintaining high cycling stability above 92% under loading and unloading for more than 10,000 cycles. Finite element numerical simulation analysis confirms that the BTO/PVDF piezoelectric thin films prepared by this process have excellent sensing performance. Integrating the device with a data acquisition and processing module can easily detect various life activities of the human body, which has great potential in flexible electronic skin, motion acquisition, and so on.