Experimental and first-principle investigation of Cu-doped ZnO ferromagnetic powders

Zn1-xCuxO powders were synthesized by using sol-gel method. Electronic band structure and ferromagnetic properties of Zn1-xCuxO powders were studied experimentally and theoretically. The simulations are based upon the Perdew-Burke-Ernzerhof form of generalized gradient approximation within the density functional theory. Zn1-xCuxO shows dilute ferromagnetism, as a saturated magnetization of 0.9x10(-3) emu/g was observed for Zn0.95Cu0.05O powders. The strong p-d hybridization between Cu and its four neighbouring O atoms is responsible for the ferromagnetism. Comparing with ZnO whose Fermi level locates at the valence band maximum, the Fermi level of the Zn1-xCuxO shifts upward into the valence band and hence the Zn1-xCuxO system exhibits theoretically a p-type metallic semiconducting property. The Zn1-xCuxO system may be a potential candidate in spintronics. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim