Room-temperature ferromagnetism in well-aligned Zn1-xCoxO nanorods

Diluted magnetic semiconductor Zn1-xCoxO nanorods with a Curie temperature higher than 350 K have been synthesized by in situ doping of Co in ZnO nanorods using a simple thermal chemical vapor deposition method. Structural analyses indicated that the nanorod possesses the single-crystalline wurtzite structure and there is no segregated cluster of impurity phase appearing throughout the nanorod. The transparence of the Zn1-xCoxO nanorods in the visible region has been examined by UV-visible absorption. The fundamental absorptions of the Zn1-xCoxO nanorods estimated from the absorption spectra do not reveal pronounced difference from that of pure ZnO nanorods. (C) 2004 American Institute of Physics.