Confirmation of room temperature ferromagnetism for Mn-doped ZnO micro-tetrapod powders
- Resource Type
- Authors
- Zhongwu Liu; Raju V. Ramanujan; C. K. Ong; S.G. Yang
- Source
- Materials Letters. 62:1255-1258
- Subject
- Permittivity
Materials science
business.industry
Mechanical Engineering
Composite number
Reflection loss
Analytical chemistry
Coercivity
Condensed Matter Physics
Spectral line
Semiconductor
Nuclear magnetic resonance
Ferromagnetism
Mechanics of Materials
Permeability (electromagnetism)
General Materials Science
business
- Language
- ISSN
- 0167-577X
Room temperature ferromagnetism in the Mn-doped ZnO micro-sized tetrapod powders, synthesized by conventional thermal evaporation, has been confirmed by static and dynamic magnetic property measurements on a large scale of bulk composite samples. A saturation magnetization of 0.02 emu/g and a coercivity of 80 Oe were obtained. No Mn or Mn-rich cluster was detected on the tetrapods by XRD and TEM analysis. The permittivity, permeability and reflection loss spectra of the Zn(Mn)O-polymer composites with various Zn(Mn)O contents have been investigated in a wide frequency range. The ferromagnetism was assumed to originate from carrier-mediated exchange coupling in the high surface density tetrapods.