Excellent energy storage and discharge performances in Na_1/2Bi_1/2TiO₃-based ergodic relaxors by enlarging the [AO₁₂] cages

Abstract

In this work, lead-free 0.86(0.93Na1/2Bi1/2TiO3-0.07BaTiO3)-0.14K1/2Bi1/2(Zn1/3Nb2/3)O3 (KBZN14) ergodic relaxor demonstrates excellent energy storage performance: Ws=6.48 J/cm3, Wr = 5.10 J/cm3, and η = 80% at a moderate field of 29.0 kV/mm,...

Ultrahigh energy storage performance of a 0.75Bi0.47Na0.47Ba0.06TiO3-0.25CaTi0.8Sn0.2O3 ceramic under moderate electric fields

“…The excellent integrated energy storage performance achieved can be related to the low tan δ, ultra-small P r , large E b , and induced polyphase nanodomains in the superparaelectric state. In comparison with numerous other energy storage ceramics, consisting of BNT-based, BT-based, NN-based, and other-based ceramics, [18][19][20][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][59][60][61][62][63][64][65] we can clearly see that at high/low electric fields, the W rec and η values are less than 5.5 J cm −3 and 90%, respectively. Encouragingly, the 0.75BNBT-0.25CTS ceramic simultaneously produces high W rec (= 5.81 J cm −3 ), ultra-high η (= 90.5%) and moderate E b , showing a more comprehensive advantage over the lead-free dielectrics reported so far, as given in Fig.…”

“…4, it can be noticed that the dielectric anomaly peaks of T s and T m are attributed to the presence of low/high temperature PNRs. 19,31 Generally, the presence of the T s dielectric anomaly peak at low temperatures is due to the thermal relaxation of R/T-phase PNRs. 10 Meanwhile, the appearance of the T m anomaly peak at high temperature is due to the transition of PNRs from R to T structures and the thermal evolution of T-phase PNRs.…”

“…18 Li et al introduced K 1/2 Bi 1/2 (Zn 1/3 Nb 2/3 )O 3 in BNBT and obtained large W rec = 5.1 J cm −3 and η = 80% at a medium electric field of 290 kV cm −1 by expanding the [AO 12 ] cage and enhancing relaxation. 19 Luo et al achieved a W rec of 4.2 J cm −3 at 280 kV cm −1 by introducing Ca 2+ and Hf 4+ ions in BNBT through enhanced breakdown field strength and refinement of grains, but the η was low at 66.7%. 20 When the η value is below 90%, a large amount of heat is generated during operation, resulting in thermal breakdown and failure of the capacitor.…”

“…The Bi 0.47 Na 0.47 Ba 0.06 TiO 3 ceramic exhibits abundant polymorphic phase boundaries between the R-phase and T-phase (MPB) over a wide temperature range. 12,18,19 Therefore, the Bi 0.47 Na 0.47 Ba 0.06 TiO 3 (BNBT) ceramic was employed as the matrix to study its energy storage performances. CaTiO 3 facilitates the formation of nanodomains and structural transformation from the R-phase to T-phase, which can regulate the R/T phase content to build polymorphic nanodomains.…”

Ultrahigh energy storage density, high efficiency and superior thermal stability in Bi0.5Na0.5TiO3-based relaxor ferroelectric ceramicsviaconstructing multiphase structures

“…6(k, l) and Table S3 † depict the comparison of W rec , h and the corresponding E between x = 0.10-0.25 and other reports on BNT-based ceramics. 7,9,13,23,26,[29][30][31][32][33][34][35][36][37][38][39][40][41][42][43] It can be seen that a simultaneous achievement of high W rec and h is relatively difficult because of the competition between various parameters. For example, the polarization of dielectrics shows a positive relationship between 3 r .…”