标题：Piezoelectric performance, phase transitions, and domain structure of 0.96(K0.48Na0.52)(Nb0.96Sb0.04)O-3-0.04(Bi0.50Na0.50)ZrO3 ceramics
作者：Zhou, Chunming; Zhang, Jialiang; Yao, Weizeng; Wang, Xuemei; Liu, Dakang; Sun, Xue
作者机构：[Zhou, Chunming; Zhang, Jialiang; Yao, Weizeng; Wang, Xuemei; Liu, Dakang; Sun, Xue] Shandong Univ, State Key Lab Crystal Mat, Sch Phys, Jinan 250100, 更多
通讯作者地址：[Zhang, JL]Shandong Univ, State Key Lab Crystal Mat, Sch Phys, Jinan 250100, Shandong, Peoples R China.
来源：JOURNAL OF APPLIED PHYSICS
摘要：Demand for replacing the current lead-based piezoelectric materials with some lead-free ones becomes increasingly strong from environmental concerns. In this article, we report the piezoelectric performance, the phase transitions, and the domain configurations of highly dense 0.96(K0.48Na0.52)(Nb0.96Sb0.04)O-3-0.04(Bi0.50Na0.50)ZrO3 ceramics prepared by two step-sintering through solid-state reaction. This material has outstanding piezoelectric properties of piezoelectric coefficient d(33) = 512 pC/N and electromechanical coupling coefficient k(p) approximate to 0.56 at room temperature. While d(33) exhibits a broad peak and is greater than 430 pC/N between -30 degrees C and 70 degrees C, k(p) depends weakly on temperature below 50 degrees C but decreases considerably with further increasing the temperature. In terms of thermal aging, both d(33) and k(p) remain stable from -50 degrees C to 240 degrees C. The degradation of k(p) quickly stabilizes in the first thermal cycle between -50 degrees C and 150 degrees C. Furthermore, the measurement of relative dielectric permittivity epsilon' upon heating indicates that rhombohedral-orthorhombic, orthorhombic-tetragonal, and tetragonal-cubic phase transitions occur at TR-O approximate to -40 degrees C, TO-T approximate to 54 degrees C, and T-C approximate to 265 degrees C, respectively. The X-ray diffraction analysis shows that the crystalline structure at room temperature is of orthorhombic-tetragonal phase coexistence. We also investigate the domain structure with an acid etching technique. The unpoled ceramic exhibits a complicated domain pattern consisting of irregularly shaped domains of long parallel stripes separated by 180 degrees domain boundaries from neighboring domains. In contrast, upon poling, the domain pattern becomes simpler and takes the form of long parallel stripes of diverse widths, with a hierarchical nanodomain structure appearing inside some of the broader stripes. We consider that the superior piezoelectric properties and reasonable temperature stability are closely related to the rhombohedral-orthorhombic and orthorhombic-tetragonal phase transitions and to the characteristic domain structure. Published by AIP Publishing.