title: Monodispersed NiO nanoflowers with anomalous magnetic behavior.
abstract: 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.
authors.affiliation: International Center for New-Structured Materials (ICNSM), Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: M Y
authors.initials: MY
authors.lastname: Ge
authors.forename: L Y
authors.initials: LY
authors.lastname: Han
authors.forename: U
authors.initials: U
authors.lastname: Wiedwald
authors.forename: X B
authors.initials: XB
authors.lastname: Xu
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: K
authors.initials: K
authors.lastname: Kuepper
authors.forename: P
authors.initials: P
authors.lastname: Ziemann
authors.forename: J Z
authors.initials: JZ
authors.lastname: Jiang