Magnetic properties of the highly iron-doped rutile TiO2 nano crystals

The highly iron-doping to the rutile TiO2 nano-crystals up to Fe/Ti = 0.2 (Ti0.833Fe0.167O2−δ) was investigated by magnetic and high-pressure annealing study. The magnetic data clearly confirmed the substitution and absence of ferromagnetic order. Instead, presence of anti-ferromagnetic interactions was detected. The high-pressure annealed pellets were revealed highly electrically insulating, reflecting electrical nature of the doped crystals. The result provides a great contrast to what was observed for the thin film form of the doped ferromagnetic TiO2.