The picture quality of a plasma display panel (PDP) is very sensitive to its phosphor characteristics, including luminance, decay time, surface charge, and longevity of the phosphor material itself. In our previous work, the discharge efficiency of a green cell in a PDP was enhanced by coating Zn2SiO4:Mn2+ phosphor with positively charged metal oxides, such as MgO or ZnO. The coated Zn2SiO4:Mn2+ phosphors were examined for stability under PDP manufacturing as well as operating conditions. It was found that Al2O3 would be the best coating material for Zn2SiO4:Mn2+ phosphor because it gives longevity as well as a stable charging effect in green cells. (C) 2008 The Electrochemical Society. [DOI: 10.1149/1.2987700] All rights reserved.