Keywords: nanosilicon, magnetic susceptibility, electron paramagnetic spectrum, ferromagnetism, nanotechnology, magnetic properties, nanoporous silicon powder, silicon nanocrystals
Magnetic properties of nanoporous Si powder
Results of magnetic susceptibility and electron paramagnetic resonance studies of porous silicon powder (g = 2.0055) obtained by electrochemical technique are presented. In comparison with diamagnetic bulk Si (χd = –2.29 × 10–7 cm³/g), the porous Si powder exhibits paramagnetic properties (χp = 1.1 × 10–5 cm³/g) with weak share of ferromagnetism (χf = 1.85 × 10–5 cm³/g). Centres of 'dangling covalent bonds' type on the surface of silicon nanocrystals were registered to be responsible for the EPR spectra. In suggestion of uniform distribution of the paramagnetic centres in powder bulk its density was estimated to be 3.5 × 1022 cm-3.