Achieving Ultrahigh Energy Storage Performance for NaNbO₃-Based Lead-Free Antiferroelectric Ceramics via the Coupling of the Stable Antiferroelectric R Phase and Nanodomain Engineering

Abstract

NaNbO 3 (NN)-based lead-free eco-friendly antiferroelectric (AFE) ceramics with an extremely high maximum polarization (P m ) are believed to be a promising alternative to traditional lead-based ceramics. Nevertheless, the high energy dissipation resulting from the large polarization hysteresis, which arises from the AFE-ferroelectric (FE) phase transition, poses a great challenge to the application of this promising ceramic. Herein, an excellent recoverable energy storage density (W rec ) was attained by intentionally designing a (0.86 − x) NaNbO 3 -0.14CaTiO 3 -xBiMg 2/3 Nb 1/3 O 3 (NN-CT-xBMN) relaxor antiferroelectric ceramic, attributed to the synergistic effect of the stable AFE R phase and nanodomain engineering to overcome the bottleneck. The obtained results illustrate that the inclusion of BMN causes the transition from AFE microdomains to nanodomains and stabilizes the relaxor AFE orthorhombic R phase, which generates a highly stable polarization field response with low hysteresis and delays the AFE-FE phase transition, thus improving energy storage density. As a consequence, a high W rec of 5.41 J cm −3 with an excellent conversion efficiency η of 86.7% was obtained in the NN-CT-0.08BMN ceramic. Moreover, the NN-CT-0.08BMN ceramic exhibits superior stability in temperature (25−150 °C), frequency (1−600 Hz), and fatigue behavior (10°−10 4 cycles) together with a large current density (C D = 810 A cm −2 ), ultrahigh power density (P D = 118 MW cm −3 ), and ultrafast discharge rate (t 0.9 < 0.7 μs). This superior energy storage density, coupled with outstanding stability, suggests that the NN-CT-0.08BMN ceramic has the potential to be a promising candidate for pulsed power applications and power electronics.

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

“…(f) Comparing values of W rec and η between ceramics x = 0, 0.20, and 0.20 (RRP). (g) Comparison of ESP parameters between this work and other lead-free ceramics. ,,,,,,,,,,,− ,− (h) Temperature-dependent (25–160 °C) and (i) frequency-dependent (1–100 Hz) P–E loops for x = 0.20 (RRP) ceramic.…”

“…Recently, many lead-free dielectric ceramic materials have been applied in energy storage systems due to their excellent thermal stability and good fatigue resistance, such as BaTiO 3 -based (BT), − NaNbO 3 -based (NN), − K 0.5 Na 0.5 NbO 3 -based (KNN), , and Bi 0.5 Na 0.5 TiO 3 -based (BNT). ,− Among them, BNT-based ceramics are considered the best candidates to replace Pb-based energy storage materials due to their high P max (>40 μC·cm –2 ) and relatively simple phase structure . According to previous reports, BNT exhibits a rhombohedral ( R , space group R 3 c ) phase structure below 255 °C, while the R phase in BNT gradually transforms into a tetragonal ( T , space group P 4 bm ) phase between 255 and 400 °C, forming a two-phase structure in which the R phase coexists with the T phase. − The R phase of BNT typically possesses high polarization, but there is a large polarization hysteresis under electric field action, causing BNT to exhibit square P – E hysteresis loops at ambient temperature. , In contrast, the T phase of BNT exhibits comparatively low polarization and high dynamic activity with small polarization hysteresis under electric field action .…”

Engineering Phase Separation in Niobate Glass through Ab Initio Molecular Dynamics for Enhanced Energy Storage Performance and Unprecedented Thermal Stability in Niobate-Based Glass Ceramics

“…It is noteworthy that the sample consistently exhibits slender P–E loops thanks to its robust thermal stability, the decrease in W rec and η remains below 3 and 4%, respectively, throughout the tested temperature range. In Figure i, a comparison of W rec and η between KBBNTP-2T GCs and various other tungsten bronze ceramics and glass ceramics is presented. − ,− Figure S13 also shows the stability of the KBBNTP-2T GCs sample in terms of different frequencies and cycle numbers. It can be seen that this sample shows a certain degree of stability.…”

High-Entropy Strategy for Improved Mechanical and Energy Storage Properties in BaTiO3–BiFeO3-Based Ceramics

“…Currently, a number of dielectric capacitor materials have been extensively investigated, such as relaxor ferroelectric (RFE), ferroelectric (FE), antiferroelectric (AFE), and linear dielectric (LD). , Large energy storage performances of AFE ceramics, such as Pb­(Zr, Hf)­O 3 , AgNbO 3 , and NaNbO 3 , are attributed to their large Δ P ( P max – P r ), which is brought about by the AFE-FE phase transition taking place at low electric fields. However, due to its opposing FE-AFE phase transition, the inevitable significant hysteresis results in generally low efficiency . From an application perspective, low energy storage efficiency translates to increased heat dissipation, which, in turn, significantly impacts the capacitors’ cycle life and dependability .…”

“…However, due to its opposing FE-AFE phase transition, the inevitable significant hysteresis results in generally low efficiency. 9 From an application perspective, low energy storage efficiency translates to increased heat dissipation, which, in turn, significantly impacts the capacitors' cycle life and dependability. 10 In contrast, dynamic polar nanoregions (PNRs) in RFE produce hysteresis-free polarization responses, endowing these materials to a good perspective in energy storage devices.…”