The crystallinity and the photoluminescent properties of spray pyrolized ZnO phosphor containing Eu2+ and Eu3+ ions Original Research Article

A europium doped ZnO (ZnO:Eu) particle was directly synthesized by the spray pyrolysis method. The crystal structure of samples was designated by the europium ion and the synthesis temperature. We identified the coexistence of Eu2+ and Eu3+ ions in the as prepared ZnO, which was strongly influenced by the doping concentration and the synthesis temperature. With addition of a 0.5 mol% concentration of europium ions, only the Eu2+ ion existed in particles, while both Eu2+ and Eu3+ ions existed in sample using 1 mol% or higher concentration of europium ions. Changing the wavelength of the excitation source, we also found that both the blue and red luminescence can be obtained.