静电纺丝制备K<sub>0.5</sub>Na<sub>0.5</sub>NbO<sub>3</sub>纳米纤维及其压电发电性能研究

Abstract

采用溶胶–凝胶静电纺丝技术制备无铅压电K0.5Na0.5NbO3 (KNN)纳米纤维，研究了退火温度和纺丝电压等对纳米纤维物相和形貌的影响。结果表明，退火处理后的纳米纤维是正交钙钛矿结构的KNN材料。随着退火温度的升高，纳米纤维的平均晶粒尺寸逐渐增大。当纺丝电压为6~12 kV时，KNN纳米纤维的直径随着电压的增大呈现先增加、后减小的趋势。将KNN纳米纤维在不同间距的叉指电极上进行组装，可获得能够输出交流脉冲电压的压电发电元件。输出电压的幅值可达190~430 mV，并随叉指电极间距的增加而增大。 The lead-free K0.5Na0.5NbO3 (KNN) nanofibers were fabricated through sol-gel electrospinning process. The effects of annealing temperature and electrospinning voltage on the phase and mor-phology of the products were investigated. The results show that the annealed nanofibers are or-thorhombic perovskite structured KNN materials. The increase of annealing temperature will lead to the increase of average grain size. When the electrospinning voltage is increased from 6 to 12 kV, the diameter of the nanofibers will be firstly increased and then decreased. By integrating the KNN nanofibers onto the interdigital electrodes, the piezoelectric generator can be obtained, which can generate impulsive alternative voltage. The amplitude of the output voltage is up to 190 - 430 mV, and will increase with the electrode spacing.