Trapping of Compensating Charges in Corona Poled PVDF Films

TL;DR

This paper investigates how charges trapped in transition zones compensate depolarizing fields in corona poled PVDF films, revealing the mechanisms of charge injection and trapping related to polarization.

Contribution

It provides experimental evidence linking polarization with space charge behavior and details the mechanisms of charge trapping in PVDF films.

Findings

Depolarizing fields are compensated by trapped charges in transition zones.

Charges are injected or thermally emitted and trapped during polarization.

Polarized and non-polarized regions are separated by these trapped charges.

Abstract

Experimental evidence is provided on close relation between polarization and space charge in corona poled PVDF films. It is shown that the depolarizing field is compensated by charges trapped in macroscopic transition zones, by which polarized parts of the volume are separated from non-polarized ones. The compensating charges are either injected in the bulk, or created inside due to the thermal emission and then trapped when the ferroelectric polarization in crystallites is formed.