Optical and electrical properties of Zn2SiO4:Mn2+ powder electroluminescent device

Green-emission Zn2SiO4:Mn2+ powder phosphor was applied for powder electroluminescence device through a screen printing method. The EL device consisted of silver nanowires as top electrode, 6 mu m-thick Zn2SiO4:Mn2+ phosphor layer, 45 mu m-thick BaTiO3 dielectric layer, and metal bottom electrode. The EL device showed the strong 525 nm green emission spectrum. Its luminance-voltage dependence showed the exponential increase, and its luminance-frequency dependence showed the linear increase and then saturation behavior. It is notable that its temperature dependence showed the constant behavior at lower temperature, and then the drastic rising pattern up to Curie temperature of the dielectric layer (similar to 120 degrees C), and then the thermal quenching trend. The maximum luminance was 0.96 cd/m(2) where the power consumption was 250 W/m(2) at 420 Vp and 400 Hz, and thus the luminous efficiency was 0.012 lm/W.