Enhanced Electrohydrodynamics for Electrospinning a Highly Sensitive Flexible Fiber-Based Piezoelectric Sensor

Abstract

The single-jet mode in an electrohydrodynamic (EHD) system is the most desirable mode for generating uniform droplets and fibers and has many applications in numerous fields. Several studies have been carried out to enhance the performance of the EHD process focusing on this mode. In this paper, we introduce the use of a chamfered nozzle in an EHD system to greatly extend the single-jet mode's voltage range, and generally, to enhance the EHD process in terms of control capability and product quality. We carried out simulations and experiments to compare the performance of a chamfered nozzle and conventional flat-end nozzle. Both theoretical analysis and experiments demonstrate that the chamfered nozzle in an EHD system reduces the critical voltage, broadens the voltage range for the single-jet mode, and enhances homogeneity in particle and fiber generation. Furthermore, the chamfered nozzle's advantages were demonstrated in fabricating highly uniform poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) fibers for piezoelectric sensor development. Owing to the fibers' excellent quality, the sensor shows high sensitivity that can detect and differentiate between the drops of a metal bead, a water droplet, and an oil droplet. The use of a chamfered nozzle with its advantages shows potential for development of better EHD-based devices.

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