Domain Engineered Lead-Free Ceramics with Large Energy Storage Density and Ultra-High Efficiency under Low Electric Fields

Abstract

Dielectric energy storage materials are becoming increasingly popular due to their potential superiority, for example, excellent pulse performance as well as good fatigue resistance. Although numerous studies have focused on lead-free dielectric materials which possess outstanding energy storage characteristics, the results are still not satisfying in terms of achieving both large discharging energy density (W d) and high discharging efficiency (η) under low electric fields, which is crucial to be conducted in miniatured electronic components. Here, we adopt the strategy of domain engineering to develop sodium bismuth titanate (Bi0.5Na0.5TiO3)-based ceramics employed in the low-field situation. Remarkably, a large W d of 2.86 J/cm3 and an ultrahigh η of 90.3% are concurrently obtained in 0.94­(Bi0.5Na0.5)0.65(Ba0.3Sr0.7)0.35TiO3-0.06 Bi­(Zn2/3Nb1/3)­O3 system when the electric field is as low as 180 kV/cm. Additionally, the ceramic shows brilliant thermal endurance (20–160 °C) and frequency stability (0.1–100 Hz) with high W d (>1.48 J/cm3) together with an ultra-high η (>90%). What’s more, the ceramic displays a fast charge–discharge time (t 0.9 = 109.2 ns). The piezoresponse force microscopy (PFM) results reveal that the introduced Bi­(Zn2/3Nb1/3)­O3 disrupts the microdomains of (Bi0.5Na0.5)0.65(Ba0.3Sr0.7)0.35TiO3 ceramics and promotes the formation of nanodomains, leading to enhanced energy storage properties. The current work may arouse interest in developing low-field high-performing dielectric capacitors for energy storage application.

Enhanced energy storage properties of hafnium-modified (0.7Ba0.55Sr0.45–0.3Bi0.5Na0.5)TiO3-based relaxor ferroelectric ceramics via regulating polarization nonlinearity and bandgap

“…22 Band C 1 and C 2 in the 500–600 cm −1 wavenumber region are intimately associated with BO 6 octahedra vibrations. 23,24 Fig. S4 (ESI†) displays the evolution of the wavenumber and intensity ratio of the two modes.…”

Superior energy storage performance in (Bi0.5Na0.5)TiO3-based lead-free relaxor ferroelectrics for dielectric capacitor application via multiscale optimization design

“…12,107 From a microscopic perspective, the shape evolution of P-E loops is closely linked with the dynamic response of PNRs, which has been observed in lead-free RFE materials. 20,108,109 To validate the domain evolution in the BNT-BAT-CT ceramics, outof-plane PFM phase, amplitude, and morphology characterization studies in scanning areas of 5 Â 5 mm 2 at a voltage of 20 V and different relaxation times are employed, as shown in Fig. 5(e)-(j), S15 and S16, † respectively.…”

Achieving Ultrahigh Energy-Storage Density with Excellent Thermal Stability in Sr0.7Bi0.2TiO3-Based Relaxors via Polarization Behavior Modulation

“…It can be clearly observed that the Raman bands between 200 and 700 cm −1 move to higher wavenumbers according to the deconvolution results, which means a strengthening of the bonding between cations and oxygen, indicating the increment of the unit cell polarity. 22,35,39 The Raman spectra and the XRD refinement both verify the polarization enhancement behavior with increasing BNT content.…”

“…Unlike the mainstream way of destroying long-range ferroelectric/antiferroelectric order to improve energy-storage properties, we have selected the end members with high P max gene to promote the polarization behavior of SBT-based ceramics. Above all, BNT end member with large P max is chosen on account of the 6s 2 lone pair electron configuration . Furthermore, we add Bi­(Mg 0.5 Ti 0.5 )­O 3 end member simultaneously possessing A-site and B-site cation displacements that is beneficial for the ferroelectricity of perovskite structure .…”

“…Above all, BNT end member with large P max is chosen on account of the 6s 2 lone pair electron configuration. 35 Furthermore, we add Bi(Mg 0.5 Ti 0.5 )O 3 end member simultaneously possessing A-site and B-site cation displacements that is beneficial for the ferroelectricity of perovskite structure. 13 2 mol % Bi(Mg 0.5 Ti 0.5 )O 3 is chosen as dopants due to the ability of maintaining the high P max and high η.…”