• PDF / 514,434 Bytes
• 6 Pages / 612 x 792 pts (letter) Page_size
• 23 Downloads / 305 Views

DOWNLOAD

REPORT

---

0902-T10-48.1

Characterization of Lead Zirconate Titanate Powders Prepared by Hydrothermal Method Lingjuan Che1, Yongping Ding2, Jinrong Cheng1*, Chao Chen1 and Zhongyan Meng1 1

School of Materials Science and Engineering, Shanghai University, Shanghai 200072, P. R. China, 2Electrical and Computer Engr, University of Minnesota, Minneapolis, MN 55455, USA ABSTRACT Lead Zirconate Titanate (PZT) powders have been synthesized by a hydrothermal method at the processing temperatures of 120-220 oC for 1.5-50 hours, based on the reaction of Pb(CH3COOH)2·3H2O, ZrOCl2·8H2O, Ti(C4H9O)4 and KOH. Hydrothermally treated PZT powders were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transformation infrared (FTIR) techniques respectively. The influences of hydrothermal synthesize conditions on the crystalline structure and the morphology of PZT particles were investigated. Crystallized PZT powders could be synthesized at the KOH concentration of >2.5 mol/l. INTRODUCTION The excellent dielectric and piezoelectric properties of Lead Zirconate Titanate (PZT) make it very useful and applicable in various electronic components, including capacitors, memories, sensors and actuators. It is well known that there are many synthesis methods such as coprecipitation [1], sol-gel [2] and the conventional solid-state reaction process to fabricate PZT powders. Among these methods, an additional calcination step is required to crystallize PZT into the perovskite structure. Moreover, this may introduce the extensive particle aggregation. In recent years, the hydrothermal synthesis has been considered as an attractive method for the formation of advanced ceramics due to the merit of low processing temperature in comparison to other processes. A variety of ferroelectric compounds have been synthesized by hydrothermal methods, such as BaTiO3 [3], PbTiO3 [4], Bi4Ti3O12 [5] and PbZrxTi1-xO3 [6]. In the hydrothermal process, crystalline powders can be directly produced from solutions. In the case of PZT, such a low temperature processing will eliminate the Pb volatilization. Furthermore, the grain size and morphologies of PZT particles can be controlled using appropriate starting materials and processing conditions [7]. Significant researches have been conducted on the hydrothermal formation of PZT powders. Most of these studies have investigated the synthesis conditions for the formation of crystalline PZT from solutions [8], and the thermodynamic stability of PZT in the hydrothermal processing [9]. However, the formation mechanism of PZT powders in the hydrothermal environment remains unclear. Traianidis et. al [10] reported different growth mechanisms for hydrothermal PZT particles, which are dependent on the initial concentration of the mineraliser and the processing temperature. In this study, the hydrothermal method was utilized to prepare crystalline PZT powders. Specially, the influence of hydrothermal processing conditions including the concentration of starting materials, reaction temperature and