Photoluminescence properties of Ba2ZnSi2O7:Eu2+, Re3+ (Re = Dy, Nd) long lasting phosphors prepared by the combustion-assisted synthesis method

Long lasting alkaline earth silicates, Ba2ZnSi2O7:Eu, Dy, Ba2ZnSi2O7:Eu, Nd and Ba2ZnsSi2O7:Eu, Dy, Nd were prepared by the combustion-assisted synthesis (CAS) method. The obtained phosphors were characterized by means of X-ray diffraction (XRD) and their photoluminescence spectrum (PSL). The emission spectrum shows a single band centered at 503 nm, which corresponds to the 4f65d1 → 4f7 transition of Eu2+. The Ba2ZnSi2O7:Eu phosphors showed blue-green afterglow (λem = 503 nm) when Dy3+ and Nd3+ ions were doped. The electron affinity (ea) value for Eu2+ in [EuO8] was calculated to be 1.63 eV. When the concentration quenching of Dy3+ and Nd3+ was over 0.07, the afterglow of the phosphors is enhanced.