P(VDF-TrFE)-Based Self-Sustained Monitoring System

Self-sustained devices, which can harvest energy from the environment, have the potential to overcome the limitations of battery-powered systems and, thus, are suitable for powering flexible or wearable electronics based on embedded microsensors. Compared with other materials used for energy harvesting, piezoelectric polymers exhibit significant advantages, such as high flexibility and durability as well as excellent stability. However, their low electricity-generating capability limits practical applications. In this work, the energy-harvesting performance of poly(vinylidene trifluoroethylene) [P(VDF-TrFE)] films with various chemical compositions and thicknesses is explored. The test circuit is connected to a picoammeter instead of an oscilloscope to maximize the energy output performance. A new self-powered sensing system is designed by switching off the microcontroller unit (MCU) to minimize power consumption rather than switching to the sleep mode. The results show that piezoelectric P(VDF-TrFE) generators meet the power consumption level of 1.1 $\mu \text{A}$ standby current and sustain the intermittent monitoring system. In addition, the system parameters, such as the generator size or the storage capacitance, are tunable, indicating the great potential of P(VDF-TrFE) to be applied to lightweight or flexible self-powered sensors.