A multi-step mechanism and integrity of titanate nanoribbons

Abstract

A one-step hydrothermal treatment of TiO₂ powders under strongly basic conditions has been used to synthesize titanate nanoribbons. The nanoparticles were thoroughly characterized using several methods including transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectrometry (XPS) to determine their morphological, structural and chemical characteristics. The influence of the nature and size of the TiO₂ precursor and of the reaction duration on the formation of the nanoribbons was investigated. The conditions required to obtain only titanate nanoribbons with a width ranging from 100 to 200 nm and several tens of micrometers in length were determined: the optimum precursor's grain size is about 25 nm and the reaction duration should be at least 20 h. Starting from our experimental results, we propose a multi-step mechanism of formation. In addition, a study of the integrity of the titanate nanoribbon structure reveals that they are made of an assembly of smaller ribbons juxtaposed and piled up on top of one another.