Synthesis, morphological-structural characterization and magnetic properties of amorphous iron (III)-oxyhydroxy-phosphate nanoparticles

The synthesis, the chemical, morphological, structural characterization and the magnetic properties of amorphous iron oxyhydroxy phosphate nanoparticles are reported. Aggregated spherical particles (diameter: 5-12 nm) are obtained showing a ferrihydrite-like behavior similar to that of the bacterial ferritin iron oxyhydroxy-phosphate core. A superparamagnetic behavior is observed with blocking temperatures ranging from similar to20 to similar to50K depending on the iron and phosphate content.