Outstanding Energy Storage Performance of NBT-Based Ceramics under Moderate Electric Field Achieved via Antiferroelectric Engineering

Abstract

Ultrahigh energy-storage performance of dielectric ceramic capacitors is generally achieved under high electric fields (HEFs). However, the HEFs strongly limit the miniaturization, integration, and lifetime of the dielectric energy-storage capacitors. Thus, it is necessary to develop new energy-storage materials with excellent energy-storage densities under moderate electric fields (MEFs). Herein, the antiferroelectric material Ag0.9Ca0.05NbO3 (ACN) was used to modify the relaxor ferroelectric material 0.6Na0.5Bi0.5TiO3–0.4Sr0.7Bi0.2TiO3 (NBT-SBT). The introduction of ACN results in high polarization strength, regulated composition of rhombohedral (R3c) and tetragonal (P4bm), nanodomains, and refined grain size. An outstanding recoverable energy density (W rec = 4.6 J/cm3) and high efficiency (η = 82%) were realized under an MEF of 260 kV/cm in 4 mol % ACN-modified NBT-SBT ceramic. The first-principles calculation reveals that the interaction between Bi and O is the intrinsic mechanism of the increased polarization. A new parameter ΔP/E b was proposed to be used as the figure of merit to measure the energy-storage performance under MEFs (∼200–300 kV/cm). This work paves a new way to explore energy-storage materials with excellent-performance MEFs.

Excellent Energy Storage Performance of Perovskite High-Entropy Oxide-Modified (Bi0.5Na0.5)TiO3-Based Ceramics

“…These factors lead to an outstanding improvement in energy storage performance. Figure presents the W rec and E b obtained in this work and those of other recently reported BNT-SBT base ceramics. ,,− It is obvious that BNT-SBT-0.3BNCBSTN synthesized in the present work exhibits significant E b and W rec compared to the other BNT-based systems, revealing that high-entropy design is a feasible approach to enhance energy storage performance.…”

Excellent Energy Storage Performance Achieved in Sr(Sc0.5Nb0.5)O3-Doped Bi0.5Na0.5TiO3-Based Lead-Free Relaxor Ferroelectric Ceramics

“…A series of Sr(Sc 0.5 Nb 0.5 )O 3 (SSN) were subsequently doped into the binary matrix BNT-NN to modulate the phase structure and disrupt the structure of the long-range ordered ferroelectric domains. Subject to ionic radius and valence limitations, Sr 2+ (1.44 Å, CN = 12) preferentially replaces Bi 3+ (1.36 Å, CN = 12) and Na + (1.39 Å, CN = 12) at the A site, and Sc 3+ (0.745 Å, CN = 6) and Nb 5+ (0.64 Å, CN = 6) preferentially replace Ti 4+ (0.604 Å, CN = 6) at the B site. − To verify the stability of the perovskite structure, we calculated the perovskite tolerance factor t according to the formula t = r A + r O 2 false( r B + r O false) , where r A , r B , and r O denote the radii of the A-site, B-site, and O ionic of the ABO 3 structure, respectively. , As the Sr(Sc 0.5 Nb 0.5 )O 3 doping content increases from 0 to 0.25, t decreases from 0.9968 to 0.9946. The perovskite tolerance factor t values range from 0.81 to 1.11, indicating that we can obtain a stable perovskite structure .…”

Structurally Regulated Design Strategy of Bi0.5Na0.5TiO3-Based Ceramics for High Energy-Storage Performance at a Low Electric Field

“…Dielectric ceramicbased capacitors must simultaneously achieve a high P max and breakdown electric field strength (E b ), and a small P r to obtain a large W rec value based on eqs 1 and 2. 6,7 (1 − x) Bi 0.5 Na 0.5 TiO 3 (BNT)-x SrTiO 3 (BNT-ST) binary solid solution lead-free ceramics are important owing to their double-like P−E hysteresis loops, easy fabrication, and large strain behavior. 8−10 The double-like P−E hysteresis loop with a high P max value of the BNT-ST ceramic system makes it a potential ecofriendly dielectric energy-storage material.…”

“…W loss represents the area enclosed inside the hysteresis loop. Dielectric ceramic-based capacitors must simultaneously achieve a high P max and breakdown electric field strength ( E b ), and a small P r to obtain a large W rec value based on eqs and . , …”