Synthesized and characterization of open-ended Ta₃N₅ nanotube arrays for the preparation of growth template

Abstract

In this article, a two-step anodization method was applied to tantalum foils to grow compact open-ended tantalum oxide nanotube arrays, which were subsequently subject to high temperature nitridation. The nitride nanotube arrays were characterized with SEM, XRD, and electrochemical tests including I-V and Mott-Schottky analysis. The phases in the nitrided nanotube arrays may consist of Ta3N5, TaN, TaN0.5, N-Ta2O, or the amorphous oxide. The duration of the second anodization step was found to play a key role on the microstructure and the carrier density of the nitride nanotube arrays. It is found that the duration of the second anodization has to be more than 20 min to obtain a specimen with a top layer of Ta3N5, which can work as a photo electrode or a template for the growth of photo catalyst nanomaterials.