Ultrawide Temperature Range with Stable Permittivity and Low Dielectric Loss in (1 − <i>x</i>)[0.90Na<sub>0.5</sub>Bi<sub>0.5</sub>TiO<sub>3</sub>‐0.10BiAlO<sub>3</sub>]‐<i>x</i>NaNbO<sub>3</sub> System
Pengrong Ren, Jiale Wang, Jiaojiao He, Yike Wang, Hailong Yuan, Yun Hao, Till Frömling, Yuhui Wan, Yonggui Shi, Gaoyang Zhao
Abstract
Abstract High‐temperature capacitors have become an important research topic recently as commercially available capacitors cannot fulfill the new requirements from industry. In this work, a new ceramic ternary system (1 − x )[0.9Na 0.5 Bi 0.5 TiO 3 ‐0.1BiAlO 3 ]‐ x NaNbO 3 is introduced, and the effects of NaNbO 3 concentration on macroscopic phase structure, locally disordered structure, dielectric properties, conduction properties, and energy storage properties are studied. At the optimum composition of x = 0.30, an ultrawide temperature range (−90 and 320 °C) covering both stable permittivity (Δε′/ε′ 25°C ≤ ± 15%) and low dielectric loss (tan δ ≤ 0.02) can be obtained. Additionally, this material has a high RC constant of 2.8 s and a high energy storage efficiency of 88% under the electric field of 60 kV cm −1 at room temperature. Therefore, this work provides a very promising candidate for dielectrics used in multilayer ceramic capacitors (MLCC) in an ultrawide operating temperature range.