Synthesis and magnetic properties of monodisperse magnetite nanocubes

The monodisperse Fe3O4 nanocubes with controllable sizes from 6.5to30.0nm have been synthesized in one pot. The shape-induced texture of the self-assembled nanocube superlattices has been deposited onto substrates by a convective assembly technique. The cubelike shapes affect the crystalline orientation of individual particles within the self-assembled superlattices compared with the nanoparticles with an isotropic spherical shape. The nanocubes with a size less than 25nm show a typical superparamagnetic behavior at room temperature. Comparison of the hysteresis loop at 5K of cubes with different sizes reveals a size-dependent behavior of saturation magnetization and coercivity.