Enhancement of Energy-Storage Density in PZT/PZO-Based Multilayer Ferroelectric Thin Films

Abstract

PbZr0.35Ti0.65O3 (PZT), PbZrO3 (PZO), and PZT/PZO ferroelectric/antiferroelectric multilayer films were prepared on a Pt/Ti/SiO2/Si substrate using the sol–gel method. Microstructures and physical properties such as the polarization behaviors, leakage current, dielectric features, and energy-storage characteristics of the three films were systematically explored. All electric field-dependent phase transitions, from sharp to diffused, can be tuned by layer structure, indicated by the polarization, shift current, and dielectric properties. The leakage current behaviors suggested that the layer structure could modulate the current mechanism, including space-charge-limited bulk conduction for single layer films and Schottky emission for multilayer thin films. The electric breakdown strength of a PZT/PZO multilayer structure can be further enhanced to 1760 kV/cm, which is higher than PZT (1162 kV/cm) and PZO (1373 kV/cm) films. A recoverable energy-storage density of 21.1 J/cm3 was received in PZT/PZO multilayers due to its high electric breakdown strength. Our results demonstrate that a multilayer structure is an effective method for enhancing energy-storage capacitors.

High Energy Storage Performance of PZO/PTO Multilayers via Interface Engineering

“…Although the energy storage density increases with the repetition period in the low electric field range, the energy storage performance of the multilayers is dominated by the breakdown strength E BDS . Compared with other reported PZO-based thin films, it can be seen that the n = 3 multilayer has superior electrical breakdown characteristics and energy storage properties over other PZO-based AFE films and multilayers, as shown in Figure d, indicating that multilayer heterostructure design is a promising method to obtain high energy storage material. − ,− …”

“…(a) Weibull distribution of the breakdown electric strength E BDS ; (b) unipolar P – E loops of multilayer films at their corresponding E BDS ; (c) energy storage density and efficiency of the multilayers depending on the electric field. (d) Comparison of energy storage density under different electric fields between n = 3 multilayer films and other films. − ,− …”

“…The heterostructure multilayer has become an important approach to tailor and improve the energy storage properties due to its remarkable improvement in breakdown strength as well as the chemical optimization. ,− It can not only make use of two different materials to directly fabricate composites but can also limit the grain growth and impede the propagation of electrical trees by blocking charge carrier motion via the heterogeneous interface. PZO-based multilayer heterostructures were reported to combine the advantage of the low remanent polarization of PZO with the high saturation polarization of ferroelectric or the slim loop of relaxed ferroelectric materials, which have attracted widespread interest in high-performance energy storage devices. − It is shown that the E BDS in the PZO/Pb 0.9 La 0.1 Zr 0.52 Ti 0.48 O 3 multilayer can be monotonically enhanced with the interface density until the single layer thickness decreases to 20 nm, where the optimum energy density property is attributed to the peak value of P m and the enhanced E BDS induced by the interface blocking effect . In Ba 0.7 Ca 0.3 TiO 3 /BaZr 0.2 Ti 0.8 O 3 (BCT/BZT) multilayers, the E BDS can also be increased from 3.3 (for N = 2) to 4.7 MV/cm (for N = 8) by hindering the propagation and growth of the electrical trees, leading to an ultrahigh energy storage density .…”

Improved Leakage Behavior at High Temperature via Engineering of Ferroelectric Sandwich Structures

“…As we know, thermal energy can aid the transport of the charge carrier and strongly influence the leakage current, and the leakage current determines the breakdown field strength and thus the energy storage performance [ 8 , 9 ]. It is exciting that, with the application of interface engineering in multilayer films, the breakdown field strength can be effectively improved, and the wide-temperature storage characteristics can be improved by constructing multilayer structures reasonably [ 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. However, the mechanism by which the structure influences the leakage current at high temperature is unclear.…”

Antiferroelectric Phase Diagram Enhancing Energy-Storage Performance by Phase-Field Simulations

“…Antiferroelectric materials have excellent energy-storage performance because of their double hysteresis loop and remanent polarization close to zero. , The antiparallel spontaneous polarization crystal structure leads to the unique dielectric response. The first theoretical justification of antiferroelectricity was provided by Kittel et al in 1951 .…”