Hydrothermal synthesis of iron phosphate microspheres constructed by mesoporous polyhedral nanocrystals

Abstract Novel monodispersed Fe 5 (PO 4 ) 4 (OH) 3 ·2H 2 O microspheres with the diameters of several micrometers were prepared by a facile one-step hydrothermal method without using any templates, only employing FeCl 3 ·6H 2 O and NaNH 4 HPO 4 as the initial materials. The obtained samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HR-TEM), respectively. The characterizations revealed that the as-prepared microspheres are constructed by the polyhedral nanoparticles with an average diameter of 100 nm. The corresponding FePO 4 microspheres assembled by mesoporous polyhedral nanocrystals can be easily obtained by calcining a sphere-like Fe 5 (PO 4 ) 4 (OH) 3 ·2H 2 O precursor.