The synthesis of zero-valent, carbon-supported nanoiron (C-Fe0) was completed through a silica-template route for the purpose of evaluating the transport behavior through sand columns with anionic homopolymers as surface-modifiers. Monodispersed, nanoporous silica spheres of 780 nm to 1.2 μm as evidenced by transmission electron microscopy and scanning electron microscopy were synthesized through hydrolysis of a silane and subsequently filled with carbon through pyrolysis of a liquid alcohol. The silica template was removed by etching with hydrofluoric acid, and the resulting porous carbon was impregnated with iron via a soluble iron salt and heated to reduce the iron species through a solid-state reaction. While the resulting C-Fe0 was of the desired composition as indicated by powder x-ray diffraction, imaging of the material showed the formation of aggregates rather than the desired monodispersed spheres necessary for a targeting study. While the silica-template route appears to be promising, further experimentation is required to impregnate the carbon support with iron without causing particle aggregation.
Two other routes to the carbon support were investigated, namely dehydration of sucrose in an autoclave and an atom spray technique. Although the dehydration method produced carbon spheres, the yield was too low to carry forward for transport studies. Investigations into the atom spray technique are currently in progress in conjunction with the Materials Science department.
