TY - JOUR
T1 - Dopant Spin States and Magnetism of Sn1−xFexO2 Nanoparticles
AU - Punnoose, A.
AU - Dodge, Kelsey
AU - Beltrán, J. J.
AU - Reddy, K. M.
AU - Franco, Nevil
AU - Chess, Jordan
AU - Eixenberger, Josh
AU - Barrero, C. A.
N1 - Punnoose, A.; Dodge, Kelsey; Beltrán, J.J.; Reddy, K.M.; Franco, Nevil; Chess, Jordan; . . . and Barrero, C.A. (2014). "Dopant Spin States and Magnetism of Sn1−xFexO2 Nanoparticles". Journal of Applied Physics, 115(17), 17B534. https://doi.org/10.1063/1.4869285
PY - 2014/5/7
Y1 - 2014/5/7
N2 - This work reports detailed investigations of a series of ∼2.6nm sized, Sn1-xFexO2 crystallites with x=0-0.10 using Mossbauer spectroscopy, x-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance spectroscopy (EPR), and magnetometry to determine the oxidation state of Fe dopants and their role in the observed magnetic properties. The magnetic moment per Fe ion μ was the largest ∼6.48×10-3 μB for the sample with the lowest (0.001%) Fe doping, and it showed a rapid downward trend with increasing Fe doping. Majority of the Fe ions are in 3+ oxidation state occupying octahedral sites. Another significant fraction of Fe dopant ions is in 4+ oxidation state and a still smaller fraction might be existing as Fe2+ ions, both occupying distorted sites, presumably in the surface regions of the nanocrystals, near oxygen vacancies. These studies also suggest that the observed magnetism is not due to exchange coupling between Fe3+ spins. A more probable role for the multi-valent Fe ions may be to act as charge reservoirs, leading to charge transfer ferromagnetism.
AB - This work reports detailed investigations of a series of ∼2.6nm sized, Sn1-xFexO2 crystallites with x=0-0.10 using Mossbauer spectroscopy, x-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance spectroscopy (EPR), and magnetometry to determine the oxidation state of Fe dopants and their role in the observed magnetic properties. The magnetic moment per Fe ion μ was the largest ∼6.48×10-3 μB for the sample with the lowest (0.001%) Fe doping, and it showed a rapid downward trend with increasing Fe doping. Majority of the Fe ions are in 3+ oxidation state occupying octahedral sites. Another significant fraction of Fe dopant ions is in 4+ oxidation state and a still smaller fraction might be existing as Fe2+ ions, both occupying distorted sites, presumably in the surface regions of the nanocrystals, near oxygen vacancies. These studies also suggest that the observed magnetism is not due to exchange coupling between Fe3+ spins. A more probable role for the multi-valent Fe ions may be to act as charge reservoirs, leading to charge transfer ferromagnetism.
UR - https://scholarworks.boisestate.edu/physics_facpubs/150
U2 - 10.1063/1.4869285
DO - 10.1063/1.4869285
M3 - Article
SN - 0021-8979
VL - 115
JO - Journal of Applied Physics
JF - Journal of Applied Physics
IS - 17
M1 - 17B534
ER -