Pure phase normalZn2GenormalO4 was fabricated by solid state reactions and the products were annealed in various atmospheres, such as O2 , air, N2 , vacuum, Zn, and Ge. The material was a native defect phosphor presenting white-bluish emission and its photoluminescence was about 40% brighter than that of the commercial ZnO phosphor. The electron paramagnetic resonance (EPR) measurements showed the existence of Zni∙ (or Zn+ ), an abnormal valence for Zn. Additionally, VO∙ , VZn′ , and ionized VGe were also detected by EPR. The model for the luminescent emission of this native defect phosphor was proposed, which may arise from the recombination between the donors ( VO∙ and Zni∙ ) and the acceptors ( VZn′ and ionized VGe ).

No abstract

No abstract