Synthesis and magnetostructural studies of amine functionalized superparamagnetic iron oxide nanoparticles

Superparamagnetic iron oxide nanoparticles are synthesized through co precipitation method by using the new generation base diisopropylamine (DIPA) which electrostatically complexes with iron ions, reduces them and subsequently caps the nanoparticle. Coating of DIPA on the surface of the nanoparticles was confirmed through FTIR and TG-DTA. We investigate the effect of reaction time as well concentration of DIPA on the particle size and magnetic properties of Fe3O4 nanoparticles. Effect of concentration of DIPA on particle size reveals that the nanocrystallite size of Fe3O4 nanoparticles increases to its maximum (the increase is nominally 5.2 nm to 8.5 nm) and then reduces (3.2 nm). Particle size and magnetic properties of the synthesized nanoparticles are also influenced by reaction time; in general as the reaction time increases the particle size increases. The lattice parameter of iron oxide nanoparticles varies from similar to 8.32 to similar to 8.39 angstrom with reaction time. From magnetic measurements, superparamagnetism of the Fe3O4 nanoparticles was confirmed. The results clearly suggest that the magneto-structural properties of Fe3O4 (or any ferrite) can be easily tuned by using DIPA.