Department of Materials Science, Sichuan University, 610064, Chengdu, P. R. China.
Phys Chem Chem Phys. 2018 Aug 1;20(30):20149-20159. doi: 10.1039/c8cp02891e.
In this study, 0.96KNNSx-0.01SZ-0.03BNZ ceramics (x = 0-0.08) were used as examples to illustrate the effects of phase boundaries on strain property and temperature stability. The addition of Sb5+ resulted in a rhombohedral-tetragonal (R-T) phase boundary at x = 0.05-0.07, as confirmed by temperature-dependent Raman spectra. In the R-T region, an improved piezoelectric constant (d33 = 390-440 pC N-1) and high unipolar strain (Suni = 0.14-0.15%) were observed due to the dominating intrinsic contribution. More importantly, a favorable temperature stability of Suni was observed in the ceramics with x = 0.05; for example, there was a slight variation of +5% to -13% when the temperature was increased from 20 °C to 180 °C. Through systematic investigations of composition and temperature-dependent strain, methods to improve Suni and consolidate its temperature stability in KNN-based ceramics were subsequently suggested. We believe that this study can promote the understanding and design of KNN-based ceramics with high strain and favorable temperature stability.
在这项研究中，以 0.96KNNSx-0.01SZ-0.03BNZ 陶瓷（x = 0-0.08）为例，说明了相界对应变性能和温度稳定性的影响。温度相关拉曼光谱证实，Sb5+的添加导致了在 x = 0.05-0.07 处存在菱方-四方（R-T）相界。在 R-T 区，由于主导的本征贡献，观察到改进的压电常数（d33 = 390-440 pC N-1）和高单轴应变（Suni = 0.14-0.15%）。更重要的是，在 x = 0.05 的陶瓷中观察到 Suni 的良好温度稳定性；例如，当温度从 20°C 升高到 180°C 时，仅略有变化（+5%至-13%）。通过对组成和温度相关应变的系统研究，随后提出了提高 Suni 并巩固其在 KNN 基陶瓷中温度稳定性的方法。我们相信，这项研究可以促进对具有高应变和良好温度稳定性的 KNN 基陶瓷的理解和设计。
