Magnetic behavior of SnO2 nanosheets at room temperature

Magnetic behavior of SnO2 nanosheets has been investigated both experimentally and theoretically. It is found that SnO2 nanosheets with a thickness of 1.5–13 nm show ferromagnetic state at ambient temperature. First-principles calculations reveal that oxygen atoms at O-terminated surface in SnO2 sheet are spin polarized, resulting in magnetic moment of 1.6 μB for pure SnO2 nanosheet while Sn atoms just beneath the O-terminated surface contribute only −0.082 μB. This study will stimulate more investigations for understanding the origin of ferromagnetic TM-doped SnO2 (TM=3d transition metals) in particular case and TM-doped semiconductor oxides in general at ambient temperature and trigger further studies for magnetic behavior of low-dimensional systems which are nonmagnetic in bulk state.