关键词: 聚偏氟乙烯, 六水合三氯化铁, 柔性传感器, 压电性, 静电纺丝

Abstract:

In order to prepare a portable flexible sensor with high sensitivity, iron (III) chloride hexahydrate(FeCl₃·6H₂O)was added to polyvinylidene fluoride(PVDF) to prepare PVDF/FeCl₃ composite fibrous membranes by electrospinning and hence the sensor. Scanning electron microscope, X-ray diffraction, Fourier transform infrared spectrometer, contact angle analyzer were used to characterize the morphology, structure, wettability, mechanical properties and piezoelectricity of the fibrous membranes. The test results show that an appropriate amount of FeCl₃·6H₂O could increase the relative content of β crystal type in the fibrous membrane and thus effectively improve the piezoelectric output of the sensor. However, too much FeCl₃·6H₂O would inhibit the formation of the β crystal type. When the mass fraction of FeCl₃·6H₂O is up to 0.5%, the ratio of β crystal type in the fiber crystal structure reaches a maximum of 68.74%, and the maximum output voltage reaches about 5 V. The response time of the sensor to the excitation process is up to 0.025 s. The response time is basically the same under different excitation frequencies, and the sensor shows higher piezoelectric output at dynamic high-frequency.

Key words: polyvinylidene fluoride, iron (III) chloride hexahydrate, flexible sensor, piezoelectricity, electrospinning