Enhancing the Energy Density of Tricritical Ferroelectrics for Energy Storage Applications

Abstract

Recently, tricritical ferroelectrics have been drawn tremendous attention, owing to their ultrahigh dielectric permittivities of up to εr > 5 × 104, and their consideration for prototype materials in the development of high-performance energy storage devices. Nevertheless, such a materials system suffers from the disadvantage of low breakdown strength, which makes its energy density far from the satisfactory level for practical application. In this paper, a material-modification approach has been reported, for improving the dielectric strength for tricritical ferroelectric materials Ba(Ti1−xSnx)O3 (BTS) through doping with Bi1.5ZnNb1.5O7 (BZN) additives. The results suggest that the electric strength has been largely improved in the modified tricritical ferroelectric material (BTSx-yBZN), and the associated energy density reaches Ue = 1.15 J/cm3. Further microstructure investigation indicates that the modified tricritical ferroelectric material exhibits homogenous fine grains with perovskite structure in crystal symmetry, and the BZN may help to form a special structure that could enhance the breakdown strength. The findings may advance the material design and development of high-energy storage materials.

Multifunctional barium titanate ceramics via chemical modification tuning phase structure

“…Figure 11C gives the distribution of W rec and η for typical lead‐free and lead‐based bulk ceramics. A similar W rec ceiling is observed in BT‐, 129,166‐190 KNN‐, 189‐193 and ST‐based ceramics 189,194 because of their similar electric‐field induced polarization. A larger W rec can be achieved in lead‐free BNT‐, 189,195,196 BFO‐, 189,197‐199 NN‐, 200,201 and lead‐based ceramics, 202‐204 due to the larger polarization or higher BDS.…”

“…Until now, the addition of Bi 3+ ‐based compounds is the most useful method to optimize the energy storage performance of BT ceramic by inducing the formation of relaxor state, such as BaTiO 3 ‐BiMO 3 , BaTiO 3 ‐Bi(M, N)O 3 , BaTiO 3 ‐(Bi, M)NO 3 , where M = Li + , Na + , K + , Zn 2+ , Mg 2+ , Al 3+ , Ni 3+ , rare‐earth ions, etc. and N = Zr 4+ , Ti 4+ , Sn 4+ , Nb 5+ , Ta 5+ , etc 129,166‐189 . As we know, Bi 3+ has a lone‐pair electronic 6s 2 configuration, being analogous to Pb 2+ , which supports large polarizability under high electric field.…”

“…B1‐B3, Evolution of ε r ‐ T curves, P ‐ E loops, and W rec , W loss and η for BT‐based ceramics with the ferroelectric phase, relaxor phase, and crossover state between them. C, Distribution of W rec and η for BT‐, BNT‐, BFO‐, KNN‐, NN‐, ST‐, AN‐, and Pb‐based ceramics 129,165‐206 . D1, ε r ‐ T curves of BaTiO 3 ‐ x K 0.73 Bi 0.09 NbO 3 (BT‐ x KBN) ceramics at 1 kHz.…”