Morphology evolution of α-Fe2O3 nanoparticles: the effect of dihydrogen phosphate anions

alpha-Fe2O3 nanoparticles with various morphologies (including spindles, rods, tubes, disks and nanorings) were synthesized under the influence of H2PO4- ions via a simply hydrothermal method. It was found that the morphologies of the alpha-Fe2O3 nanoparticles were highly sensitive to the concentration of H2PO4- ions. The special all doubly coordinated surface hydroxyl configuration on (001) facets of alpha-Fe2O3 was the most important factor for the morphology evolution. The final morphologies of the samples mainly depend on how the H2PO4- anions oriented the growth of the (001) facet. All morphologies of the synthesized alpha-Fe2O3 nanoparticles could be systemically evaluated by the competition of Fe3+ and H2PO4- ions on the (001) facets.