Ferromagnetic order in substitutional Fe-doped In2O3 powder

We report an experimental investigation of the room-temperature ferromagnetism of an Fe-doped In₂O₃ system. (In_1−xFe_x)₂O₃(x = 0.00, 0.02, 0.06,0.10,0.14 or 0.18) powders were prepared by a standard solid-state reaction method followed by sintering in air at 1200 °C for 48 h. The influence of Fe-doping concentration on the structural and magnetic properties of the In₂O₃ samples was studied. X-ray diffraction analysis reveals that Fe ions are incorporated into the In³⁺ sites of the In₂O₃ lattice without altering the cubic bixbyite structure. Magnetic characterization shows ferromagnetic behavior at room temperature for all the Fe-doped In₂O₃ samples. The observed ferromagnetism is attributed to the oxygen vacancies induced by substitution of Fe into In³⁺ sites and vacuum annealing. A model of ferromagnetic exchange interactions was proposed to explain the ferromagnetism in this system.