P‐50: Morphology and Luminescence Property of Gd 2−x Y x O 3 :Li, Eu (0.0 × 0.8), Red‐Phosphor with High Efficiency at Low Voltages

The single phased Gd 2−x Y x O 3 :Li, Eu solid‐solution was successfully prepared by a citrate method at 650. Such a temperature is much lower than the typical solid‐state reaction or spray pyrolysis temperature (> 1300). However, additional heat treatment up to 850 ∼ 900 was required to obtain the optimum optical properties. Photoluminescence (PL), cathodoluminescence (CL), and morphology of Gd 2−x Y x O 3 :Li, Eu system were compared as a function of x values. The PL and particularly CL emission intensities at low‐voltages (< 1 kV) of this solid‐solution were 50 ∼ 80 % higher than those of commercial red phosphor Y 2 O 3 :Eu in the range of 0.0 × 0.8. This phosphor material appears to be very promising for field emission display (FED) because the particle size and shape are easily controlled at low temperature (900) by the change of Y or Li contents without any significant loss of brightness.