Fabrication and Characterization of K_(0.5)Na_(0.5)NbO_3 Nanotube Arrays by Sol-Gel AAO Template Method

K0.5Na0.5NbO3(KNN) nanotube arrays were synthesized by Sol-Gel processing with anodic aluminum oxide templates,using Nb(OC2H5)5,CH3COOK and CH3COONa as the starting materials and 2-methoxyethanol(2-MOE) as solution.The precursor gel was analyzed by thermogravimetric-differential thermal analysis.The phase,morphology and microstructure of KNN nanotube arrays were characterized by X-ray diffraction,scanning electron microscope(SEM) and transmission electron microscope(TEM),respectively.The as-prepared samples are monoclinic phase perovskite structure with the outer-diameter of about 200 nm and wall thickness of about 20 nm.Polarization-electricfield(P-E) response curves of KNN nanotube arrays show that the remanent polarization(Pr) and the coercive electricfield(Ec) are about 1.86 μC/cm2 and 0.68kV/cm,respectively.