A new modulated structure in α-Fe₂O₃ nanowires

A new modulated structure consisting of periodic (1120) stacking faults (SFs) in the α-Fe₂O₃ nanowires (NWs) formed by the thermal oxidation of Fe foils is reported, using a combination of high-resolution transmission electron microscopy (HRTEM) observations and HRTEM image simulations. The periodicity of the modulated structure is 1.53 nm, which is ten times (3300) interplanar spacing and can be described by a shift of every ten (3300) planes with 1/2 the interplanar spacing of the (1120) plane. An atomic model for the Fe₂O₃ structure is proposed to simulate the modulated structure. HRTEM simulation results confirm that the modulated structure in α-Fe₂O₃ NWs is caused by SFs.