Preparation and luminescence properties of novel K2ZnP2O7: Mn2+ green phosphor

Novel green-emitting phosphors K2Zn1 − xP2O7: x mol% Mn2+ have been successfully prepared using classical solid-state reaction method in air atmosphere, doped by different Mn2+ ion contents, namely x = 0.5, 1, 1.25 and 1.5 mol%. The samples were characterized by the thermogravimetric (ATD/ATG/DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), steady and time-resolved photoluminescence techniques. It was found that all K2Zn1 − xP2O7: x mol% Mn2+ samples crystallize in the tetragonal phase with P42/mnm space group. Upon 425 nm excitation, K2ZnP2O7: Mn2+ exhibits an intense broad green asymmetric emission band peaking at 520 nm, owing to the 4T1→6A1(6 S) transition of Mn2+ ion in K2ZnP2O7. In addition, it is suggested that Mn2+ ions occupy more than one symmetry site in the host K2ZnP2O7. The optimal Mn2+ ion concentration in K2ZnP2O7:Mn2+ phosphor is 1 mol % and with the lifetime 9.81 ms.