Cathodoluminescence change of YNbO4 : Bi phosphor after acid treatment

Abstract

The reason for the cathodoluminescence (CL) change of YNbO4:Bi after acid treatment is determined. It is observed that after acid treatment. the CL intensity of YNbO4:Bi decreased to a value below that of the untreated one at excitation energies lower than 1 keV. However. YNbO4:Bi was brighter than the untreated one at an excitation energy of 1 keV or higher. Meanwhile, ZnGa2O4 was compared with YNbO4:Bi in terms of luminescence properties. After acid treatment. ZnGa2O4 showed the same trend as YNbO4:Bi at excitation energies lower than 1 keV. However. the luminescence intensity of ZnGa2O4 did not increase at an excitation energy of 1 keV or higher. It was found that surface modification using an acid increases the luminescence efficiency of YNbO4:Bi by realizing stoichiometric composition at the phosphor surface.