Modulated band structure and phase transitions in calcium hafnate titanate modified silver niobate ceramics for energy storage

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

“…S14†) also serve as the main intrinsic and extrinsic contributors for significantly boosted E b value in BNT-BAT-0.4CT ceramic. It is clear that the designed materials show large potential in the achievements of intrinsic and extrinsic factors for improving E b , which are comparable to state-of-the-art reported lead-free ceramic systems, such as BNT-based (electrical resistivity ∼150 × 10 3 Ω cm at 500 °C), 48 BF-based ( G a ∼0.7 μm, E g ∼2.8 eV, electrical resistivity (400 °C) ∼0.2 MΩ cm), 8 NN-based ( G a ∼1 μm), 5,20 and AN-based ( G a ∼1.5–2 μm, E g ∼2.76–2.95 eV, O v /(O v + O L )∼0.12) 19,100 ceramics. These achieved good parameters are thought to be responsible for the high E b value, as confirmed from Fig.…”

“…As shown in Fig. 5(l) and (n), complex domain patterns with randomly scattered PNRs are clearly observed along [100] c and [110] c , suggesting a local-structure inhomogeneity. 8 The randomly distributed elliptically shaped PNRs exhibit a small size range of $1.2-2.8 nm, which are comparable with those observed in other lead-free ceramics with high energy-storage properties.…”

Achieving Ultrahigh Energy Storage Density in Lead-Free Sodium Niobate-Based Ceramics by Modulating the Antiferroelectric Phase

“…Figure summarizes the W rec , η, and E b values of newly reported NaNbO 3 -, Bi 0.5 Na 0.5 TiO 3 -, BaTiO 3 -, BiFeO 3 -, and AgNbO 3 -based lead-free dielectric ceramics. ,,,,− Of note, the synergistic improvement of W rec (>10 J/cm 3 ) and η (>80%) has been a significant long-term challenge for lead-free ceramic capacitors (Figure a). Specifically, relaxor ferroelectric ceramics can easily achieve high η (>80%) because of their superior dielectric relaxor behavior, while W rec is seriously restricted by their relatively low E b (<60 kV/mm, Figure b).…”

Achieving Ultrahigh Energy Storage Density of La and Ta Codoped AgNbO3 Ceramics by Optimizing the Field-Induced Phase Transitions

“…Later, Li et al reported on the La 3+ doping-induced suppression of the long-range antiferroelectric order and diminishing ferroelectricity in AgNbO 3 ceramics, which resulted in a giant value of the W rec (∼7 J/cm 3 ) under a 476 kV/cm electric field . Numerous studies have been conducted also to investigate the effect of the B-site substitution on the energy storage properties of AgNbO 3 . − For instance, the B-site substitution with tantalum was found to reduce the polarizability at B-sites and decrease the grain size, yielding the enhanced antiferroelectricity and improved dielectric breakdown strength . More recently, a simultaneous doping of the A- and B-sites has been reported to be an effective approach to increase the W rec and η of AgNbO 3 . − Lu et al have increased the E F field and substantially reduced the domain size and correlation length of the antiferroelectric/ferroelectric coupling in AgNbO 3 ceramics by an introduction of Nd 3+ ions into A-sites and, at the same time, Ta 5+ ions at B-sites, which resulted in a high W rec of 6.5 J/cm 3 …”