Title :
The structure and magnetic properties of NiO with different sizes
Author :
Yi, J.J.B. ; Ding, J. ; Thongmee, S. ; Feng, Y.P. ; Chow, G.M.
Author_Institution :
Dept. of Mater. Sci. & Eng., Nat. Univ. of Singapore, Singapore
Abstract :
NiO was prepared by co-precipitation followed by an annealing. The fabricated powers showed cluster structures when the annealing temperature was 170degC and the powders showed a dominant ferromagnetic coupling with a magnetization of 105 emu/g. When the annealing temperature was higher than 170degC, the powders showed a nanocrystalline structure composed of surface spins and antiferromagnetic core. Exchange bias was observed after field cooling in these powders. Spin glass and superparamagnetism behaviors were found in the cluster NiO and nanocrystalline NiO, respectively.
Keywords :
annealing; magnetisation; nanostructured materials; precipitation; spin glasses; superparamagnetism; NiO; annealing; antiferromagnetic core; cluster structures; co-precipitation; exchange bias; ferromagnetic coupling; magnetic properties; magnetization; nanocrystalline structure; spin glass; superparamagnetism; temperature 170 degC; Annealing; Antiferromagnetic materials; Cooling; Couplings; Magnetic cores; Magnetic properties; Magnetization; Nanostructures; Powders; Temperature;
Conference_Titel :
Nanoelectronics Conference, 2008. INEC 2008. 2nd IEEE International
Conference_Location :
Shanghai
Print_ISBN :
978-1-4244-1572-4
Electronic_ISBN :
978-1-4244-1573-1
DOI :
10.1109/INEC.2008.4585663
