Monodispersed NiO nanoflowers with anomalous magnetic behavior.
Nickel oxide (NiO) nanoflowers, prepared by thermal decomposition, exhibit anomalous magnetic properties far below the blocking temperature, i.e., a cusp in both the zero-field-cooled and field-cooled curves at about 21 K. Detailed characterization discloses that the individual NiO nanoflower consists of porous crystals with holes (1.0-1.5 nm in size) inside. We believe that the low temperature magnetic feature observed here could be a new kind of spin transition for the uncompensated spins around the holes and will trigger more studies in other nanostructured antiferromagnetic materials.
Ge
M Y
MY
International Center for New-Structured Materials (ICNSM), Zhejiang University, Hangzhou, People's Republic of China.
Han
L Y
LY
Wiedwald
U
U
Xu
X B
XB
Wang
C
C
Kuepper
K
K
Ziemann
P
P
Jiang
J Z
JZ