Application of ferroelectric materials for improving output power of energy harvesters

Abstract

In terms of advances in technology, especially electronic devices for human use, there are needs for miniaturization, low power, and flexibility. However, there are problems that can be caused by these changes in terms of battery life and size. In order to compensate for these problems, research on energy harvesting using environmental energy (mechanical energy, thermal energy, solar energy etc.) has attracted attention. Ferroelectric materials which have switchable dipole moment are promising for energy harvesting fields because of its special properties such as strong dipole moment, piezoelectricity, pyroelectricity. The strong dipole moment in ferroelectric materials can increase internal potential and output power of energy harvesters. In this review, we will provide an overview of the recent research on various energy harvesting fields using ferroelectrics. A brief introduction to energy harvesting and the properties of the ferroelectric material are described, and applications to energy harvesters to improve output power are described as well.

Paramagnetic Transitions Ions as Structural Modifiers in Ferroelectrics

“…For Cr þ3 the spin states could be ½ and 3=2, corresponding to weak and medium crystalline field split respectively. The Cr þ2 is no paramagnetic by the 1s 2 2s 2 2p 6 3s 2 3p 6 4s 0 3d 4 electronic configuration, i.e., had four paired electrons in d-orbital, this is because we have a octahedral crystalline structure into the perovskite structure that causes electronic levels split (Zero field splitting); this split have a high energy levels separation and the electrons unfollows Hund's rule, see Figure 6(A), this causes that electrons stays at lowers energy levels, all this is because the experimental g-values are less than 2.00 for all spectrum, Sr 2þ is substitute for Pb 2þ in perovskite structure of the material [1][2][3][4][25][26][27]. Additionally, in Figure 14 shows how Cr is introduced to substitute Ti in sites B for the samples [8,[25][26][27].…”

“…The ferroelectric materials are very important for technological applications in general, like sensor and actuators they are important part of electronic devices. The temperature, pressure, electric and electromagnetic field nonlinear response of ferroelectrics make them ideals like active elements due to pyroelectric and piezoelectric effects [1][2][3][4]. Ferroelectrics are used like ultrasonic generator; high voltage transforms and accelerators [1][2][3][4], also, they are using in optical components, piezoelectric transducers, and pyroelectric sensors [1][2][3][4].…”

“…The partial or total substitution of Pb or Ti produces modified compounds with new electrical polarization and modifies their structure depending of doping atoms and the interactions material [8]. The changes in the structure could be small or big depending to the kind of dopand and the percentage of them [1][2][3][4][5][6][7][8]. If the dopand is a paramagnetic ion it could be detected by paramagnetic resonance (EPR) and it is capable to sense structure changes principally by spin-orbit interactions [9][10][11].…”

“…Figure 6.Splittings and degeneracies of orbital levels d1 or d6 ions in two types of electric field caused by negative charges for (A) octahedral field (∆ > 0) plus tetragonal distortion and (B) tetrahedral field (∆ < 0) plus tetragonal distortion. For d4 and d9 ions applieds to octahedral and tetrahedral fields. Shifting of the center of gravity of the set of levels is ignored[9][10][11][12][13][14][15].…”

Interfacial Dipole Modulation Device With SiOX Switching Species

“…ARIOUS non-volatile memory devices for replacing Sibased vertical flash memory have been studied [1]- [15]. Memory devices based on interfacial dipole modulation (IDM) involving dipole switching between high- materials and SiO2 have been proposed [16] owing to their material compatibility with CMOS technology, amorphous phase at low process temperature (≤ 350 ˚C), and low dispersion.…”