Fe2O3 nanostructures on SrTiO3(111) by chemical vapor deposition: Growth and characterization

Fe2O3 nanostructures were grown on SrTiO3(1 1 1) substrates by chemical vapor deposition. The material morphology and crystal structure were significantly affected by the growth temperature. In fact, the metastable, scarcely investigated epsilon-Fe2O3 polymorph was obtained as a pure phase at 400 degrees C, whereas a transition to alpha-Fe2O3 took place at 500 degrees C. The synthesized systems, characterized by a high purity and homogeneity, underwent a remarkable morphological evolution as a function of the growth temperature, ranging from columnar nanoarrays to dense pyramidal-like nanodeposits. For the first time, the optical properties of CVD-derived epsilon-Fe2O3 nanomaterials have been characterized, revealing an efficient absorption in the Vis range. In addition, magnetic force microscopy suggested that spin domains were formed in the obtained systems.