PZT–NZF/CF ferrite flexible thick films: Structural, dielectric, ferroelectric, and magnetic characterization

Abstract

The preparation and properties of thick flexible three-phase composite films based on lead zirconium titanate (PZT) and various ferrites (nickel zinc ferrite (NZF) and cobalt ferrite (CF)) were reported in this study. Properties of three-phase composite films were compared with pure polyvinylidene fluoride (PVDF) and PZT-PVDF films. X-ray diffraction data indicated the formation of well crystallized structure of PZT and NZF/CF phases, without the presence of undesirable phases. Scanning electron micrographs showed that the ceramic particles were dispersed homogeneously in the PVDF matrix and atomic force microscopy confirmed that the size of the particles is around 30 nm. Non-saturated hysteresis loops were evident in all samples due to the presence of highly conductive ferrite phases. Under magnetic field of 10 kOe, composite films exhibited a typical ferromagnetic response. Dielectric properties were investigated in the temperature range from-128 to 250 ℃ and frequency range of 400 Hz-1 MHz. The results showed that the value of dielectric constant of the PVDF/PZT/ferrite composites increased about 25% above the one obtained for pure PVDF.

Porous, multi-layered piezoelectric composites based on highly oriented PZT/PVDF electrospinning fibers for high-performance piezoelectric nanogenerators

“…Piezoelectric effect refers to the phenomenon in which the material without a center of structural symmetry changes its internal polarization with external pressure, giving rise to the same amount of heterogeneous charges on the surface. At first, perovskite piezoelectric ceramics ((K, www.springer.com/journal/40145 Na,Li)NbO 3 [1,2], BaTiO 3 [3], and Pb(Zr,Ti)O 3 [4,5]) and piezoelectric semiconductors (ZnS [6], ZnO [7], and CdS [8]) attracted lots of attention due to their excellent piezoelectric coefficients, but the brittleness of their own limited the application in flexible electric devices. On the contrary, piezoelectric polymer has good flexibility but much lower piezoelectric coefficient comparing to the piezoceramics/semiconductors.…”

Recent advances in electrospun magnetic nanofibers and their applications

“…22 Only when the thermal disturbance is lower than the exchange interaction can magnetic order be formed. There are three main types of magnetic order structures, namely ferromagnetic (FM) order, [23][24][25][26][27][28][29] antiferromagnetic (AFM) order 23,26,[30][31][32] and ferrimagnetic (FI) order. [33][34][35][36] Among them, the exchange interaction in the FM material forces the spins to be arranged in the same direction, so the material exhibits strong magnetism.…”

Porous, Multi-layered Piezoelectric Composites Based on Highly Oriented Pzt/pvdf Electrospinning Fibers for High-performance Piezoelectric Nanogenerators

“…Piezoelectric effect refers to the phenomenon in which the material without a center of structural symmetry changes its internal polarization with external pressure, giving rise to the same amount of heterogeneous charges on the surface. At rst, perovskite piezoelectric ceramics ((K,Na,Li)NbO 3 [1,2], BaTiO 3 [3] and Pb(Zr,Ti)O 3 [4,5] and piezoelectric semiconductors (ZnS[6], ZnO [7] and CdS [8]) attracted lots of attention due to their excellent piezoelectric coe cients, but the brittleness of their own limits the application in exible electric devices. On the contrary, piezoelectric polymer has good exibility but much lower piezoelectric coe cient comparing to the piezoceramics/semiconductors.…”