Photoluminescence of white ZnS-based phosphor with Pr and Mn activators prepared by complementary blending and codoping

摘要

In this study, white ZnS-based phosphors were prepared by two different methods, i.e., codoping with Pr and Mn activators and blending complementary phosphors of ZnS:Pr and ZnS:Mn. KC1 flux doping was used to enhance the crystalline growth of the phosphor. Photoluminescence excitation measurements showed that the excitation energy was absorbed by the ZnS host, and then efficiently transferred to the Pr~(3+) and Mn~(2+) ions. The energy transfer between the host and Pr~(3+) was more efficient than that between the host and Mn~(2+). However, the energy transfer between Pr~(3+) and Mn~(2+) was relatively inefficient. The CIE coordinates were (0.36, 0.32) for the white ZnS:Mn,Pr phosphor with a brightness of 17.9 cd/m~2, and (0.35,0.32) for the white ZnS:Pr blended ZnS:Mn phosphor with a brightness of 25.4 cd/m~2. The emission color of the codoped phosphor was significantly altered by varying the doping concentration of the activator, whereas the emission color of the blended phosphor was relatively more stable when the blending weight ratio of the complementary phosphor was varied.