Spherical magnetite (Fe3O4) clusters with a wormhole-like mesopore structure was successfully synthesized using a single iron precursor and a nonionic amphiphilic triblock copolymer as the structure-directing and pore-forming agent. In this synthesis method, the interaction between the iron precursor and the triblock copolymer self-assemblies in ethanol leads to the assembly of spinel-structured nanocrystals into spherical mesoporous clusters. To study the chemical composition, morphology, crystal information, and properties of the synthesized material, a variety of techniques is employed, including FT-IR, XPS, FE-SEM, HR-TEM, 57Fe M�ssbauer spectroscopy, and WXRD, confirming the formation of pure-phase magnetite particles with monodisperse morphology (about 130 nm in diameter), 3-D wormhole-like mesopores, and highly crystalline spinel structure. In addition, a reasonable model for the formation mechanism of these spherical clusters is proposed and discussed in more detail, based on the analysis of results. The mesoporous magnetite has a high specific surface area of 165.6 m2 g-1, and relatively large pores with a mean size of 5.2 nm. The magnetic susceptibility data demonstrate that this material exhibits superparamagnetic behavior.

Assembly of magnetite nanoparticles into spherical clusters with a 3D mesopore channels

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.