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Silver niobate (AgNbO 3 , AN) dielectric ceramics and their antiferroelectric behavior have attracted increasing attention for their potential applications in energy-storage capacitors. However, AN's inferior dielectric breakdown strength, recoverable energy storage density, and efficiency have limited its application. In this work, a combination of chemical composition design and liquid-phase sintering was considered for the fabrication of highly insulated and desensitized AN-based ceramics for enhancing E b , W rec , and η of AN. We design and prepare (1 − x)AgNbO 3 - x (Sr 0.7 Bi 0.2)HfO 3 (AN-100 x SBH, x = 0.00–0.06) ceramics with the addition of 1 mol% BaCu(B 2 O 5) (BCB) as a sintering aid to realize this. It is found that highly desensitized ceramics can be formed at 1000–1030 °C over the course of 2 h. The electrical property characterization results indicate that the AFE state and E b are significantly enhanced with increasing SBH concentration. High W rec and η values of 6.1 J/cm3 and 73%, respectively, under an applied field of 330 kV/cm are achieved in the AN-5.5SBH ceramic. Meanwhile, the AN-5.5SBH ceramic shows excellent thermal stability over a wide temperature range (25–120 °C) under an externally applied field of 290 kV/cm, in which the fluctuations of W rec and η are 3.8% and 1.5%, respectively. These results provide an effective method for obtaining AN-based ceramics with excellent electrical properties under a lower sintering temperature than that required for pure AN ceramics. This method could be further generalized to develop new lead-free energy-storage dielectric materials. • AgNbO3-based dielectric ceramics with stabilized antiferroelectricity synthesized. • Ceramics with dense microstructure successfully sintered at 1000–1030 °C for 2 h. • High recoverable energy storage density (6.1 J/cm3) and efficiency value (73%) achieved. • Energy storage properties stable over the temperature range of 25–120 °C. [ABSTRACT FROM AUTHOR]

Ceramics of 0.2 wt% Mn-doped (1- x)AgNbO 3 - x CaTiO 3 (x = 0.00–0.04) were prepared in flowing oxygen with the solid state method. The microstructure, antiferroelectricity and energy storage performance were investigated to explore the potential for use in energy storage capacitors. Incorporation of CaTiO 3 in AgNbO 3 effectively inhibits the grain growth and gives rise to high dielectric breakdown strength. The temperature-dependent dielectric property and Raman spectroscopy measurements demonstrate the enhanced stability of antiferroelectricity by CaTiO 3 addition through adjusting the M 1 – M 2 phase transition. As a result of both improved antiferroelectricity and dielectric breakdown strength, a high recoverable energy density of 3.7 J/cm3 was achieved in the 2 mol% CaTiO 3 -modified AgNbO 3 ceramic, which represents one of the highest recoverable energy density in recently studied lead-free ceramics. Furthermore, the energy storage performance displays an excellent thermal stability with a low variation (3%) over a wide temperature range (20–120 °C). These results indicate that modifying AgNbO 3 simultaneously on the A- and B-sites in the ABO 3 perovskite structure may lead to the discovery of new antiferroelectric materials with a high energy density. • Enhanced stability of antiferroelectricity by CaTiO 3 addition. • High recoverable energy density of 3.7 J/cm3 in the 2 mol% CaTiO 3 -modified AgNbO 3 ceramic. • Excellent thermal stability with low variation (3%) over a wide temperature range (20–120 °C). [ABSTRACT FROM AUTHOR]