Highly transparent lead‐free (1‐x)K_0.5Na_0.5NbO₃–xSr(Zn_1/3Nb_2/3)O₃ (KNN–xSZN) ferroelectric ceramics have been synthesized via a conventional pressureless sintering method. All samples are optically clear, showing high transmittance in the visible and near‐infrared regions (~70% and ~80% at 0.5 mm of thickness, respectively). This exceptionally good transmittance is due to the pseudo‐cubic phase structure as well as the dense and fine‐grained microstructure. In addition, a high energy storage density of 3.0 J/cm³ has been achieved for the 0.94K_0.5Na_0.5NbO₃–0.06Sr(Zn_1/3Nb_2/3)O₃ ceramics with submicron‐sized grains (~136 nm). The main reason is likely to be the typical relaxor‐like behavior characterized by diffuse phase transition, in addition to the dense and fine‐grained microstructure. This study demonstrates that the 0.94K_0.5Na_0.5NbO₃–0.06Sr(Zn_1/3Nb_2/3)O₃ ceramic is a promising candidate of lead‐free transparent ferroelectric ceramics for new areas beyond transparent electronic device applications.

中文翻译：

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无铅（K，Na）NbO3基陶瓷，具有高光学透明性和强大的储能能力

通过常规的无压烧结方法合成了高度透明的无铅（1 x）K _0.5 Na _0.5 NbO ₃ – x Sr（Zn _1/3 Nb _2/3）O ₃（KNN– x SZN）铁电陶瓷。所有样品都是光学透明的，在可见光和近红外区域显示较高的透射率（在0.5 mm的厚度下分别为〜70％和〜80％）。这种极好的透射率是由于伪立方相结构以及致密细晶粒的微观结构。此外，对于0.94K _0.5 Na，已实现3.0 J / cm ³的高储能密度_0.5 NbO ₃ –0.06Sr（Zn _1/3 Nb _2/3）O ₃陶瓷，具有亚微米级晶粒（〜136 nm）。主要原因可能是除了具有致密细晶粒的微观结构外，还具有典型的弛豫样行为，其特征是弥散相变。这项研究表明，0.94K _0.5 Na _0.5 NbO ₃ –0.06Sr（Zn _1/3 Nb _2/3）O ₃陶瓷是无铅透明铁电陶瓷的有前途的候选者，其应用范围超出了透明电子设备应用的新领域。