Synthesis of ThO2 nanostructures through a hydrothermal approach: influence of hexamethylenetetramine (HMTA) and sodium dodecyl sulfate (SDS)

Abstract

In this work, ThO₂ nanostructures with various morphologies are synthesized through a hydrothermal approach. The influences of some experimental parameters, such as the concentration of hexamethylenetetramine (HMTA), the amount of sodium dodecyl sulfate (SDS) and the hydrothermal temperature, on the synthesis and morphologies of ThO₂ nanostructures were systematically investigated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The results showed that ThO₂ nanospheres with a particle size of 59 ± 9 nm could be synthesized at a molar ratio of Th⁴⁺/HMTA of 0.3 under the reaction temperature of 100 °C. Adding SDS could adjust the diameter of ThO₂ nanospheres from 240 to 71 nm while keeping other parameters constant. Furthermore, nanoparticles and the aggregated nanostructures of ThO₂ could be obtained by varying the concentration of HMTA and the amount of SDS. The possible formation mechanism of various ThO₂ nanostructures was also proposed.