Room Temperature Ferromagnetismin Co-doped ZnO Bulks

摘要

Pure single phase of Zn0.95Co0.05O bulks were successfully prepared by solidstate reaction method.The effects of annealing atmosphere and temperature on the room temperature ferromagnetic behavior were investigated. The results show that the airannealed samples has similar weak ferromagnetic behavior with the assintered samples, but the obvious ferromagnetic behavior is observed for the samples annealed in vacuum or Ar/H2 gas, indicating that the strong ferromagnetism is associated with high oxygen vacancies density. High saturation magnetization Ms=0.73 μB/Co and eoercivity Hc=233.8Oe are obtained for the Ar/H2 annealed samples with pure single phase structure when annealing temperature is 600 ℃.