Low temperature and size controlled synthesis of monodispersed γ-Fe2O3 nanoparticles by an epoxide assisted sol-gel route

Monodispersed gamma-Fe2O3 nanoparticles were prepared by a procedure-simple and precursor-cheap route, epoxide assisted sol-gel method. The gamma-Fe2O3 nanoparticles were obtained by the reaction of FeCl2 in ethanol solution with propylene oxide to form the sol, following by the boiling of the solution. As compared with other metal ions of +2 formal charge, the unexpected acidity of FeCl2 in ethanol solution assure the formation of sol. As an advantage, the unique chemistry of this route results in the low temperature of synthesis, leading to the extremely small particle size of 2.3 nm and non-aggregation state of the particles.