Perovskite oxide nanotubes: synthesis, structural characterization, properties and applications

Perovskite oxides exhibit a wide range of functional properties, such as ferroelectricity, piezoelectricity, pyroelectricity, non-linear dielectric behavior, as well as multiferroic property. These properties are indispensable for applications in microelectronic devices. Recent advances in science and technology of perovskite oxides have resulted in the feature sizes of microelectronic devices down-scaling into nanoscale dimensions. At the nanoscale perovskite oxides display novel physical properties that are different from their bulk and film counterparts. Understanding these size effects of perovskite oxides at the nanoscale is of importance for the developing a new generation of revolutionary electronic nanodevices. Due to these effects being dependent on the structure and finite size, considerable efforts have been made in the controllable synthesis of low-dimensional perovskite nanostructures such as perovskite oxide nanotubes (PONTs). PONTs can not only be used as building blocks for miniaturized microelectronic devices, but also offer fundamental scientific opportunities for investigating the intrinsic size effects of physical properties. This review article describes the recent progress made in the field of PONTs, which covers their synthesis, structural characterization, properties and applications. We begin this review with a comprehensive survey on the research activities on PONTs, and then focus on their synthesis strategies. Structural characterization and multifunctional properties of the PONTs prepared by the template synthesis are also summarized. Their potential applications in 3D memory devices, nano-scale fluidic control systems, nanoscale power generators and terahertz generators, are discussed. Finally, we conclude this review by providing our perspectives to the future directions of PONTs.