A method for quantitatively separating the piezoelectric component from the as-received Piezoelectric signal

Polymer-based piezoelectric devices are promising for developing future wearable force sensors, nanogenerators, and implantable electronics, etc. The electric signals generated by them are often assumed as solely coming from the piezoelectric effect. However, triboelectric signals originated from contact electrification between the piezoelectric devices and the contacted objects can produce non-negligible interfacial electron transfer, which is often combined with the piezoelectric signal to give a triboelectric-piezoelectric hybrid output, leading to an exaggerated measured piezoelectric signal. Herein, a simple and effective method is proposed for quantitatively identifying and extracting the piezoelectric charge from the hybrid signal. The triboelectric and piezoelectric parts in the hybrid signal generated by a poly(vinylidene fluoride)-based device are clearly differentiated, and their force and charge characteristics in the time domain are identified. This work presents an effective method to elucidate the true piezoelectric performance in practical measurement, which is crucial for evaluating piezoelectric materials fairly and correctly. Difficulties in separating tribo and piezoelectric hybrid signals can lead to an overestimated contribution of the latter. Here, authors propose a method to separate these hybrid signals in the time domain, precisely extracting piezoelectric charge transfer for performance evaluation.

Automated summary

A simple and effective method is proposed to quantitatively identify and extract the piezoelectric charge from hybrid signals, elucidating the true performance of piezoelectric devices.