Controlled Synthesis of β-FeOOH Nanorods via a Facile Hydrothermal Route

Rod-shaped β-FeOOH was synthesized through a well controlled hydrothermal reaction of FeCl3and NH2CONH2. By varying the preparatory conditions such as NH2CONH2concentration and reaction parameter we could establish precise control on the morphology of the sample. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were used to characterize the as-prepared products. The results showed the aspect ratio and mean size of theβ-FeOOH nanorods was achieved systematic control by regulating the concentration of urea. When the experimental time increased to 96h, the morphology of the resulting β-FeOOH changed from rod to nanocubes. Furthermore, the resulting rod-shaped iron hydroxides were transformed into pseudocube α-Fe2O3by increasing the synthesis temperature at 160°C.