Synthesis of ferric oxyhydroxide nanoparticles and ferric oxide nanorods by reflux assisted coprecipitation method and comparative study of their thermal properties

Haematite (Fe₂O₃) nanorods are synthesized by reflux assisted coprecipitation method in two steps. In the first step, spherical nanoparticles of ferric oxyhydroxide (FeOOH) are synthesized. In the second step, FeOOH nanoparticles are converted into Fe₂O₃ nanorods by calcination of 4 h. These products (FeOOH and Fe₂O₃) are subjected to x-ray diffractometry to analyze their lattice structure, lattice parameters, diffraction planes and miller indices. Both of these products are also subjected to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to analyze their morphology. SEM and TEM observations have revealed that products are monodisperse and hollow. The dimensions of FeOOH nanoparticles and Fe₂O₃ nanorods are also measured from SEM and TEM observations. The heat transport properties of FeOOH are compared with that of Fe₂O₃. The value of thermal conductivity, thermal diffusivity and specific heat of FeOOH and Fe₂O₃ are measured to analyze their heat transport/storage characteristics. These products are also used as fuel additive.