Ferromagnetism in Cu-doped ZnO nanoparticles at room temperature

A study of structural, optical and magnetic properties of Zn0.97−xCuxCr0.03O diluted magnetic semiconductors

“…However, for the case of Zn 0.94 Cu 0.03 Cr 0.03 O, the secondary phase of Cu emerged, which indicates that the Cu ions and Cr ions would not only substitute the Zn place but also exist as interstitial ions or enter into vacancies. As a whole, the atoms are rearranged and placed on the equilibrium state due to the coulomb interaction between Zn 2+ and O 2− , so the lattice constants abnormally increase [27,1].…”

“…Therefore, we chose Cr and Cu as doping elements, because unlike many other metals, Cr itself is anti-ferromagnetic and an extrinsic ferromagnetism cannot be induced even if Cr clustering occurs [26]. In addition, Cu is a preferred choice to avoid controversies since the secondary phases such as CuO, Cu 2 O or Cu clusters are non-ferromagnetic, which may make the interpretation of ferromagnetism in ZnCuO easier [2,27,28].…”

Enhanced room temperature ferromagnetism and photoluminescence behavior of Cu-doped ZnO co-doped with Mn

“…The point defects such as interstitial, oxygen vacancies created by TM doping played a crucial role in mediating the room temperature ferromagnetism (RTFM) [4]. The ZnO based material showed ferromagnetic ordering only when the n-type conductivity of ZnO could be converted into p-type [5][6][7]. In addition, it was found that Cu is able to convert the conductivity of ZnO from n-type to p-type.…”

Cu- and Ni-Doping Effect on Structure and Magnetic Properties of Fe-Doped ZnO Nanoparticles

“…Among transition metal, ZnO doped with Fe ions without any modification of the structure has been the most considerable interest. Ferromagnetism with Curie temperature higher than room temperature has been observed in Fe-doped [9][10][11][12], Co-doped [13][14][15], Mn-doped [16][17][18], Ni-doped [19][20][21], Cu-doped [22] and V-doped [23] ZnO nanoparticles. Meanwhile, several codoped ZnO have also been reported with the expectation that codoping can lead to remarkable changes in the properties of the materials [24][25][26].…”