Monodisperse α-Fe2O3 nanoplatelets: Synthesis and characterization

Polymer free and uniformly sized monodisperse α-FeOOH (geothite) and α-Fe2O3 (hematite) nanoplatelets have been successfully synthesized by a hydrothermal process and thermal treatment of the as-prepared α-FeOOH, respectively, using ferric aqueous solution and urea as surfactant. The as-prepared hematite and geothite phases were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Brunauer–Emmett–Teller (BET) surface area analysis and UV–vis diffuse reflection spectroscopy (DRS). The results showed that the α-Fe2O3 nanoplatelets are homogenous in size with large surface area and nanoscale thickness. The nanoplatelets length, width and thickness are respectively 300, 100 and 10 nm. High magnification SEM images show that the as prepared nanoplatelets are formed by intimate linking of nanorods through their long facets. A formation mechanism of the nanoplatelets was proposed. These nanoplatelets exhibit a high BET surface area of 69 m2/g, strong absorption of visible light and good photocatalytic degradation of methylene blue (MB) under simulated solar irradiation.