Enhanced Energy‐Storage Properties of Lanthanum‐Doped Bi_0.5Na_0.5TiO₃‐Based Lead‐Free Ceramics

Abstract

A series of Bi(0.5−x)Lax(Na0.82K0.18)0.5Ti0.96Zr0.02Sn0.02O3 (BNKTZS‐xL) (x=0–0.18) lead‐free ceramics were designed and fabricated by using a conventional solid‐state sintering method. The effects of the La3+ content on the properties of the BNKTZS‐xL ceramics were systematically investigated. Temperature‐dependent dielectric constant curves displayed two depressed anomalies, which resulted in significantly improved dielectric temperature stability. The polarization–electric field hysteresis loops illustrated that the addition of La3+ markedly enhanced the breakdown strength, energy‐storage density, and energy‐storage efficiency. A maximum energy‐storage density of 1.95 J cm−3 was obtained for the material with x=0.10, and the energy‐storage efficiency significantly improved from 28 to 85 % upon increasing the value of x from 0 to 0.18. These properties indicate that the BNKTZS‐xL ceramics may be promising lead‐free materials for high energy‐storage capacitor applications.

Ultrahigh energy storage density and charge‐discharge performance in novel sodium bismuth titanate‐based ceramics

“…36 The first anomaly is related to the relaxation of R3c-and P4bmstructured polar nanoregions (PNRs), and the other anomaly is the absolute maximum dielectric peak at the T m . [38][39][40] T m decreases gradually as x increases, which is the same as the fluctuations of the curves for dielectric loss. Besides, the modified Curie-Weiss law could be expressed as: 41 where ε max is the maximum dielectric constant, C is a constant, T m is the temperature at which the dielectric constant reaches the maximum, and γ is the degree of diffuseness.…”

“…The low‐temperature T s anomaly is frequency‐dispersive and the high‐temperature T m is frequency‐independent 36 . The first anomaly is related to the relaxation of R 3 c ‐ and P 4 bm ‐structured polar nanoregions (PNRs), and the other anomaly is the absolute maximum dielectric peak at the T m 38‐40 . T m decreases gradually as x increases, which is the same as the fluctuations of the curves for dielectric loss.…”

Enhanced Dielectric Energy Storage Performance of 0.45Na0.5Bi0.5TiO3-0.55Sr0.7Bi0.2TiO3/AlN 0–3 Type Lead-Free Composite Ceramics

“…Comparison of (a) W rec vs η and (b) E vs W rec of NBT-SBT/6AlN composite ceramics with other reported NBT-based ceramics ,,− ,,− …”

High‐Energy Storage Density and Efficiency of the xBi(Mg2/3Nb1/3)O3‐(1 − x)(Ba0.8Sr0.2)TiO3 (0.08 ≤ x ≤ 0.14) Lead‐Free Perovskite Structured Ceramics

“…Figure 7 presents W rec and η of some popular lead-free ceramics. [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] It could be seen that the W rec value of the 0.1BMN-0.9BST ceramics was at an intermediate level, and η was at a very high level.…”

“…To conclude, the 0.1BMN-0.9BST ceramics exhibited a high W rec value of 2.03 J cm À3 and a relatively high η value of 96.8% under a breakdown electric field of 250 kV cm À1 . Figure7presents W rec and η of some popular lead-free ceramics [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34]. It could be seen that the W rec value of the 0.1BMN-0.9BST ceramics was at an intermediate level, and η was at a very high level.For most energy storage capacitors, the operating temperature range is generally À55-125 °C; especially, a high operating temperature would cause thermal breakdown of energy storage capacitors.…”