Dendrite-like self-assembly of magnetite nanoparticles on porous silicon

The co-precipitation of magnetite nanoparticles in the presence of hydroxyl-functionalized porous silicon samples helps in forming the self-organization of magnetite nanoparticles into dendrite or fractal structures yielding new magnetic composites. The fractal patterned porous silicon sample with a hydroxyl terminated surface was used as a substrate for the deposition of magnetic Fr3O4 nanoparticles. This process was performed by the co-precipitation of magnetic particles from the solution of iron (Fe 3+/Fe2+)salts in the stoichiometric ratio (Fe 3+/Fe2+=2) using aqueous ammonia in the presence of the porous silicon substrate. The mechanism of fractal formation involves a DLA growth model influenced by porous-substrate effect. These new magnetic silicon composites may be used as potential applications in biotechnology as biomagnetic implants in medicine and substrate in cell biology.