Co-doped Zno Nano-powder Preparation And Research

With the rapid developing of technology and integrated circuits, various electronic devices need semiconductor materials with good performance. Diluted magnetic semiconductor, which has novel magneto-optical, magneto-electricity and magnetic transport properties has a great prospect in the fields of aviation and aerospace. Great attention has been paid on the study of diluted magnetic semiconductor, which has good magnetic properties.In this thesis, Co-doped and Co, Cu-codoped ZnO diluted magnetic semiconductor powder was prepared by the Sol-gel method. The room temperature ferromagnetism of Zn1-xO:Cox samples were achieved successfully. The micro-structure, morphology and magnetic properties of the prepared samples were characterized by XRD, SEM and VSM, respectively. The experimental results indicate that Co doping has no effect on the crystal structure of ZnO, but the crystalline quality of the Co-doped ZnO was reduced with the increasing of doping concentration. SEM measurement results revealed that the grain size of the Co-doped ZnO increased with the doping concentration. VSM measurement shows that the magnetism becomes poorer with the increasing of doping concentration. Moreover, Co, Cu-codoped ZnO sample remains the hexagonal wurtzite structure, but the morphology of the co-doped ZnO sample has some changes. VSM measurement reveals that the co-doped ZnO sample is paramagnetic.The magnetic analysis shows that the ferromagnetism of the Co-doped ZnO does not come from the second impurity phase, it is the intrinsic property of the Co-doped ZnO. For the Co, Cu-codoped ZnO sample, it is paramagnetic. This is due to that the CuO was antiferromagnetic and it is produced in the process of doping.