Ferromagnetic properties in undoped and Cr-doped SnO2 nanowires

We presented detailed characterizations of the ferromagnetic properties of undoped and Cr-doped SnO2 nanowires synthesized by chemical vapor deposition. All the samples exhibit room-temperature ferromagnetism. Our experiments reveal that, in addition to the contribution of surface oxygen vacancies, Cr doping into SnO2 plays an important role in tuning the ferromagnetism of SnO2 nanostructures. Doping the SnO2 nanowires with 1.8 at.% Cr enhances the magnetization by 28%. We applied the bound magnetic polaron model to successfully explain the enhancement of ferromagnetism.