Nanotubes consisting of Ni-particles covering the walls of porous silicon

摘要

Ni-nanostructures are electrochemically deposited within the pores of mesoporous silicon. The porous silicon template is fabricated with straight and separated pores. The geometry of the metal deposits can be tuned in a wide size range between 50 nm and a few micrometers and thus specimens with specific magnetic properties can be achieved. Furthermore small Ni-particles between 3 and 6 nm in size can be precipitated on the pore walls with various distances. In the case of a closely packed distribution the particle arrangement results in metal tubes which cover the pore walls. The superparamagnetic Ni-particles forming such a tube are magnetically interacting which leads to a ferromagnetic behavior of the system.