The Effect of Li, Cu and Zn Doping on the Luminance and Conductivity of Blue ZnGa 2O 4 Phosphor

This study investigates the doping effect of Li, Cu or Zn on the luminescence and conductivity characteristics of ZnGa 2 O 4 phosphor. The X-ray diffraction (XRD) patterns reveal a negligible difference in peak positions and values of full-width at half maximum (FWHM) under various synthetic parameters, indicating that an excellent solid solution exists between the additives and the ZnGa 2 O 4 phosphor. Doping of Li or Zn increases the oxygen vacancy concentration in the phosphor. Therefore, Li or Zn doping enhances the luminance and conductivity of ZnGa 2 O 4 phosphors. However, doping of Cu ions increases the scattering and trapping probabilities of electrons, thereby decreasing the conductivity, and results in a decreased luminescence of ZnGa 2 O 4 phosphor. As-prepared low-voltage phosphors show blue-emission, appropriate to the application in the field emission display (FED).