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 ZnGa2O4 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 ZnGa2O4 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 ZnGa2O4 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 ZnGa2O4 phosphor. As-prepared low-voltage phosphors show blue-emission, appropriate to the application in the field emission display (FED).