Synthesis and characterization of sponge-like α-Fe microtubes

Sponge-like magnetic α-Fe microtubes have been prepared via reduction of α-Fe2O3 microtubes in hydrogen flow. α-Fe2O3 microtubes have been previously obtained by combined sol-gel and template methods. It is shown that the strongly acidic aqueous medium leads to specific interaction of ferric hydroxide nanoparticles with cellulose template. This contributes to the formation of α-Fe2O3 microtubes, which retain the features of the initial fibers structure. Both calcination at high temperature (1200 °C) and reduction does not lead to the destruction of the tubular morphology. The resulting magnetic materials have a promising applications in biomedicine, as micro-reactors, microwave absorbing materials, easily recoverable from the reaction medium catalysts of various chemical reactions (including carbon nanotubes growth) and a component for creating new composite (e.g., metal-oxide) materials with improved performance characteristics.