Role of valence-band Co 3d states on ferromagnetism in Zn1−xCoxO nanorods

Abstract

This work investigates the electronic and ferromagnetic properties of Zn1−xCoxO nanorods using x-ray absorption, x-ray magnetic circular dichroism, and scanning photoelectron microscopy methods. The magnetic moment of Co ions in Zn1−xCoxO nanorods is found greatly reduced relative to that of the Co metal. The intensities of valence-band features near the valence-band maximum/Fermi level (EF) of ferromagnetic nanorods are substantially larger than those of weaker ferromagnetic nanorods, suggesting that the occupation of near-EF valence-band Co 3d states is important in determining the ferromagnetic behavior in Zn1−xCoxO nanorods.