Nanoscale Detection of Interfacial Charge Mobility in BaTiO₃/Polyvinylidene Fluoride Nanocomposites

Abstract

Polymer-based dielectric composites with inorganic oxide fillers could exhibit synergistic physical and chemical characteristics from both advantages, which have flexible applications in electrical and electronic technology. As composites with various substances, the interfacial structure plays a key role in the electric and dielectric properties. In this work, BaTiO3 particles were embedded in polyvinylidene fluoride (PVDF) by a solution crystallization process. The conductivity and dielectric constant of the composites increased with the increase of the BaTiO3 filler contents. The charge injection and dissipation behavior at the nanointerface of the composite is investigated by Kelvin probe force microscopy. It is found that the charges are more easily injected into the nanointerface between the particle and the polymer. The accumulation and dissipation of surface charges obey the exponential law. The space-charge polarization is also suggested to be a key factor of injection, while the charge dissipation is determined by charge tunneling. The result also demonstrates that the strong interfacial polarization between the BaTiO3 particles and the PVDF matrix plays a crucial role in the dielectric properties. This work provides significant insights into understanding the interfacial charge transport in dielectric composites.

Enhanced Breakdown Strength of Ferroelectric Polymer Films for Capacitive Energy Storage by Incorporating Oriented Fluorographene

“…That means that the interface features almost remain unchanged with the increase in FG loading. The value of E in our results coincides well with previous reports of polymer nanocomposites. , This interface is small in thickness yet strong in its effect on the overall dielectric performance of polymer nanocomposites, covering polarization behaviors, local electric field, charge transport, and electric treeing as will be further discussed later. ,, …”

“…37,41 This interface is small in thickness yet strong in its effect on the overall dielectric performance of polymer nanocomposites, covering polarization behaviors, local electric field, charge transport, and electric treeing as will be further discussed later. 15,43,44 The typical fracture morphologies of films are also characterized by SEM, as shown in Figure 4. Both the neat P-o-FG-0.0 sample and the P-o-FG-0.2 sample exhibit a dense fracture surface without any defect.…”

Reduced Polyaniline-Modified NaNbO3 Nanowire/Polyetherimide Nanocomposites for Dielectric Capacitors with Enhanced Dielectric Properties and High Thermal Stability

“…The key to maximizing the energy density of the final capacitors, according to classical electromagnetic theory, is to increase both the dielectric constant and E b of the dielectric materials. , The composite strategy employing high dielectric constant ceramics and high E b polymer is an efficient method to obtain synergistic improved dielectric properties, hence achieving high energy density . So far, numerous ceramic particles including BaTiO 3 , CaCu 3 Ti 4 O 12 , and boron nitride have been widely studied for dielectric applications. − Among them, owing to the field-induced reversible transitions between antiferroelectric and ferroelectric phases, the antiferroelectric ceramics with a high power density and low remnant polarization exhibit excellent energy storage features . Specifically, due to the net-zero spontaneous polarization (high P max – P r value) and environmentally friendly merits, the excellent lead-free antiferroelectric ceramic NaNbO 3 (dielectric constant ∼300) has received dramatic attention in recent years. − NaNbO 3 is also the most likely to be commercialized due to its advantages such as low bulk density and the absence of potassium …”

Effects of Ionic Liquid Content on the Electrical Properties of PVDF Films by Fused Deposition Modeling

“…Polyvinylidene fluoride (PVDF) is a semi-crystalline piezoelectric polymer with the presence of at least five crystalline phases: α, β, γ, θ, and ξ [ 3 , 4 ], of which α, β and γ are the three most common phases, α is a thermodynamically stable phase and is not electrically active, and the β and γ phases have extensive spontaneous polarization and good electrical activity. The increase in polar phase content improves the dielectric and ferroelectric properties of PVDF.…”