Characteristics of Ce0.6Tb0.4MgAl11O19 phosphor powders prepared by high temperature flame spray pyrolysis

Flame spray pyrolysis was introduced to prepare Ce0.6Tb0.4MgAl11O19 phosphor powders. The flow rates of fuel and carrier gas were optimized to prepare the Ce0.6Tb0.4MgAl11O19 phosphor powders with fine size, spherical shape and filled morphology. To produce the Ce0.6Tb0.4MgAl11O19 phosphor powders with fine size, spherical shape and filled morphology, the diffusion flame with high temperature is required to melt completely the precursors. The optimum flow rates of propane and oxygen used as fuel and carrier gas were each 4 and 10 L/min. The powders directly prepared by flame spray pyrolysis had bimodal size distributions of nano-sized and submicron-sized powders with different compositions. However, the composition of post-treated Ce0.6Tb0.4MgAl11O19 phosphor powders was similar in comparison with that of the spray solution. The CTMA phosphor powders prepared by flame spray pyrolysis had higher photoluminescence intensities than those of the phosphor powders prepared by conventional spray pyrolysis.