Ferroelectric and dielectric properties of Bi₃.₁₅Nd₀.₈₅Ti₃O₁₂ nanotubes

Abstract

In order to match the high-density requirement of ferroelectric memories, ferroelectric Bi₃.₁₅Nd₀.₈₅Ti₃O₁₂ nanotubes with outer diameter of about 100 nm and wall thickness of about 30 nm were synthesized using a sol-gel method. Transmission electron microscope images and Raman spectra revealed the Bi-layered perovskite structure of these nanotubes. Their dielectric constant and remnant polarization were comparable with those of thin film form. Piezoelectric hysteresis loops of individual nanotube measured by piezoresponse force microscope indicate their asymmetry, and the switched nanotubes show long term retention.