电泳沉积PNN-PZT陶瓷厚膜及其电学性能研究

利用电泳沉积法分别在Al₂O₃/Pt和Pt金属基底上制备了厚度为10~40μm的0.3Pb(Ni_1/3Nb_2/3)O₃-0.7Pb(Zr,Ti)O₃(PNN-PZT)厚膜, 研究了pH值、Zeta电位与PNN-PZT悬浮液稳定性的关系, 探索了沉积电压、沉积时间与电泳沉积量的关系. 结果表明, 当添加少量分散剂聚乙二醇时, pH值在3.5~5.5较宽的范围内, 悬浮液具有较高的Zeta电位, 容易制得稳定的悬浮液. 沉积电压为21V, 沉积时间为5min时, 在Pt金属基底上电泳沉积得到的PNN-PZT厚膜, 经过1200℃烧结30min后, SEM显微结构分析表明, 厚膜致密, 晶粒得到充分生长. 电学性能测试显示此厚膜具有良好的铁电介电性能, 其剩余极化强度Pr可达20.8μC/cm², 介电损耗tanδ为3.2%.

Electrophoretic Deposition and the Electrical Properties of the PNN-PZT Thick Films

0.3Pb(Ni_(1/3)Nb_(2/3))O_3-0.7Pb(Zr,Ti)O_3 (PNN-PZT) thick films (10-40μm) were prepared by electrophoretic deposition method on Al_2O_3/Pt plates and Pt metallic foils. The effect of pH value on the stability of PNN-PZT suspensions was studied by measuring the zeta potential. The relationship among the deposition voltage, time and the quality of PNN-PZT films were investigated. When the pH value is in the range of 3.5-5.5, the suspension with the 2wt% PEG is stable. When the deposited voltage and time are 21V and 5min, respectively, the PNN-PZT thick films deposited on the Pt foil are uniform and free of crack. After sintering at 1200℃ for 30min, the PNN-PZT films with high density are obtained. The PNN-PZT thick films show the high ferroelectric and dielectric properties with the remnant polarization of 20.8μC/cm~2 and the loss tangent of about 3.2% at 1 kHz. And the frequency dependences of the dielectric spectra of the PNN-PZT thick films show the relaxor property. The piezoelectric constant calculated from the S-V curve tested using the SPM is 67pm/V.