Achieving outstanding temperature and frequency stability in NaNbO₃-modified (Ba_0.94Li_0.02La_0.04)(Mg_0.04Ti_0.96)O₃ pulse energy storage ceramics

Abstract

A novel binary pulse energy-storage ceramics of the (1-x)(Ba0.94Li0.02La0.04)(Mg0.04Ti0.96)O3-xNaNbO3 system were designed and prepared utilizing solid-state reaction route and filming technology. The conspicuous frequency stability, temperature stability and anti-fatigue feature...

Effective regulation of breakdown strength through the synergistic effect of defect chemistry and energy band engineering in Ba0.85Ca0.15Zr0.1Ti0.9O3-based lead-free ceramics

“…Apart from the extrinsic factor of smaller grain size, broadening the band gap width ( E g ) is also an effective way to improve the E b . 34,49,50 The E g values can be estimated based on UV-vis absorption spectra (Fig. 7(a)) and the Tauc eqn (6): 31,34 ( αhv ) 2 = A ( hv − E g )where α , h , and v are the absorbance coefficient, Planck constant, and frequency, respectively.…”

“…The average E b value displays a maximum value of ∼574.3 kV cm −1 and ∼681.7 kV cm −1 for B 2/3 MT8 and B 2/3 ZT8 ceramics, which are higher than that of BMT8 (∼435.2 kV cm −1 ), BZT8 (∼620.2 kV cm −1 ) and most of the BT-, Sr 0.7 Bi 0.2 TiO 3 - (SBT), NN-, and BNT-based ceramics reported in the literature. 3,5,7,9,10–13,15,25,26,29–32,38,39,50–57 The improved E b induced by Bi 2/3 (M 1/3 Ta 2/3 )O 3 doping can be attributed to several aspects: (i) defect chemistry engineering increases the insulation resistivity of ceramics, which inhibits the transportation of conductive carriers (oxygen vacancies); (ii) the wider band gap of Ta 2 O 5 (∼4 eV) can enlarge the energy gap and effectively decrease the leakage current and energy loss at a high electric field, leading to improved intrinsic breakdown strength; 3,17 and (iii) the high quality ceramics feature relatively small grain size and high density (>95%), favorable for dielectric breakdown behavior as a result of the high resistivity of grain boundaries. 7,31,51…”

(Sb0.5Li0.5)TiO3-Doping Effect and Sintering Condition Tailoring in BaTiO3-Based Ceramics

“…As a result of heterovalent ions doping and adding SLT, the long-range ordered ferroelectric domains are destroyed and PNRs are formed due to the different valence states and ionic radius [34]; then, the P-E hysteresis loops of all samples become long and narrow, indicating that the relaxation property is improved, ferroelectricity is reduced and high energy storage efficiency will be possessed [33]. For each sample, the increase in E makes P max scale up and P r fluctuate slightly, stemming from the greater polarization response to the larger electric field [38]. According to Equation (1), the W rec value will increase accordingly.…”

“…As we know, all the dipole moments gradually turn to the electric field and the polarization becomes saturation during the charge process. Then, the switched dipole moments suddenly go back to the initial state and release energy [38]. On the other hand, the larger electric field and the smaller dipoles are helpful to the high-speed conversion of dipoles.…”

“…Such curves show the occurrence of peaks with an increasing electric field, which is related to the strength and degeneration of internal resistance. The enhanced driving force obtained from the increased electric field will make the carriers readily move [38]. To further understand the influence of sintering temperature and composition on the discharge mechanism, the discharge current and discharge density of different compositions at different sintering temperatures under the same electric field of 30 kV/cm are displayed in Table S2.…”