Characterization of passivated iron nanoparticles by x-ray absorption spectroscopy

Core/shell nanoparticles with both metallic iron and iron boron cores were synthesized via the reverse micellar method and characterized by x-ray absorption spectroscopy, employing x-ray absorption near edge structure and extended x-ray absorption fine structure in an integrated fashion. The particles were found to comprise an amorphous iron boron phase, a disordered iron oxide phase, and, in some cases, a crystalline bcc metallic iron phase.