Structure and magnetism of V-doped SnO₂thin films: effect of the substrate

First-principle study of magnetism in Co-doped SnO2

“…There are some experimental evidences associating the presence of oxygen vacancies with the existence of ferromagnetism in TM-doped SnO 2 [11,13,15,25]. Since the tetravalent Sn 4+ ion is substituted by divalent Co 2+ , there are intrinsic oxygen vacancies in Co-doped SnO 2 to compensate this charge difference.…”

“…The charge state of Co in Co-doped SnO 2 has been determined to be +2 by using both X-ray photoelectron spectroscopy (XPS) [11][12][13] and X-ray absorption spectroscopy (XAS) [8]. High temperature ferromagnetism was also reported in SnO 2 doped with V [14,15], Cr [7,16,17], Mn [7,18], Fe [7,17,[19][20][21][22] and Ni [7,[23][24][25]. It was found that the FM properties of TM-doped SnO 2 are sensitive to the sample preparation methods and conditions.…”

“…Archer and Gamelin's work shows that the ferromagnetism of colloidal Ni-doped SnO 2 nanoparticles can be activated by interfacial oxygen vacancies [25]. Recently it has been shown that vacuum annealing strongly influence the ferromagnetism of Co-doped SnO 2 films [13] and nanocrystalline V-doped SnO 2 films [15].…”

The role of Co impurities and oxygen vacancies in the ferromagnetism of Co-doped SnO2: GGA and GGA+U studies

“…The high-temperature ferromagnetism in TM-doped SnO 2 films was first reported by Ogale et al [6], who reported a high Curie temperature of 650 K and a giant magnetic moment of 7.5 m B /Co in a 5% Co-doped thin film sample. Room-temperature ferromagnetism was subsequently reported in SnO 2 doped with V [14,15], Cr [7,16,17], Mn [7,18,30], Fe [7,[17][18][19][20][21][22] and Ni [7,[23][24][25]. Co-doped SnO 2 system has been investigated most extensively and room-temperature ferromagnetism was found in Co-doped SnO 2 films and nano-particles prepared by a variety of growth methods [7][8][9][10][11][12][13]20,[26][27][28][29][31][32].…”

“…More and more experimental results suggest that oxygen vacancies play a crucial role in the ferromagnetism of TM-doped SnO 2 . Recently it is shown that depositing under different oxygen partial pressure [13,24] and annealing under different atmospheres [13,15] strongly influence the ferromagnetism of TM-doped SnO 2 films. Hays et al [11] found that substitution of Sn ions with Co ions result in the reduction in the oxygen content of ferromagnetic Co-doped SnO 2 powders.…”