Study of printed polymeric flexible energy harvesting elements – impact of the electrode materials and patterns

Abstract

In this paper is presented study of flexible pressure piezoelectric energy harvesting developed with an screen-printing of polyvinylidene fluoride-trifluoroethylene (P(VDF-TrFE)) ink on three different metal electrodes (silver, gold and aluminium) with three different topologies – rectangular, meander and side comb. The influence of the electrode type and pattern is studied in terms of polymer coating distribution and morphology, piezoelectric voltage generation and stability at multiple bending, as well as piezoelectric coefficient. The elements are studied at low mass loading of up to 100 g and frequency up to 50 Hz. They produce voltage between 916 and 362 mV from active area of 1 cm2 and piezoelectric polymer film of 3 μm, according to the electrode metal nature and shape. It was found that the silver electrode with meander shape is the optimal for electrical performance and mechanical stability giving superior piezoelectric coefficient of 0.332 V.m/N to the reported values and only 8.6 % decrease of the piezoelectric voltage at 1500 repeating bending cycles.

Pyroelectric Properties of BaxSr(1−x)TiO3/PVDF-TrFE Coating on Silicon

“…As a general trend, it can be noted that the produced pyroelectric voltage from these devices was greater than that produced from the devices with aluminum electrodes. The higher pyroelectric voltage can be explained by the closer work function of the silver to the Fermi level of the used ferroelectric coatings compared to the aluminum [ 19 ]. Thus, the energy level alignment resulted in the formation of an interface barrier with a lower energy height, which facilitated the charge carriers’ collection with the silver electrodes.…”

Impedance Spectroscopy of Lead-Free Ferroelectric Coatings

“…All piezoelectric samples were fabricated with near to ohmic contacts to avoid a measurement error caused by the interface barriers voltage drop. It was previously established that for piezoelectric films of GZO, the most appropriate electrode material was silver (Ag), for KNbO 3 , aluminum (Al) and for BST:PVDF-TrFE composite, Ag [20,21]. The top electrodes were patterned by lift-off process to produce a variety of similar segments for impedance spectroscopy probing.…”